Retell AI vs Bolna

Agent ops

1. ai-native userMy coding agent can provision a complete voice agent end to end — create the agent, attach a number, and place a call — through the API, CLI, or MCP without touching the dashboard

   weight 3 · round to Bolna
   Retell AI~partialprobed6/10

   Retell ships an official Node/Python SDK with full voice endpoint coverage, a CLI for managing agents and phone numbers, and an MCP server whose meta-tools (list/get/invoke_api_endpoint) expose the entire API — including agent create/update/publish — to MCP clients like Cursor or Claude Code, and a keyless runtime probe confirms the MCP handshake works end-to-end. However, the flagship quick-start walkthrough is dashboard-centric (create in UI, assign number in 'configuration settings', test/call via dashboard button), and no evidence explicitly shows a CLI/API/MCP call sequence that attaches a number and places a live call without touching the UI. Missing for 10: an explicit end-to-end CLI/MCP example showing number-attach and call-placement commands, and independent confirmation that non-dashboard number provisioning/outbound calling works in practice.

   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”
   • [claimed-docs] “Retell supports the Model Context Protocol (MCP) so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude D…”
   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [claimed-docs] “Assign your agent to the number in the configuration settings”

   proof ↗⚑ flag

   Bolna✓fullprobed8/10

   Bolna offers all three surfaces needed for agent-native provisioning: a documented API quickstart to create an agent, attach a number, and place a call (bolna-docs-14, bolna-docs-15), a native Go CLI to manage agents, calls, and phone numbers from the terminal (bolna-docs-16, bolna-probe-4), and an official MCP server to connect Claude/Cursor/Windsurf clients (bolna-docs-17, bolna-probe-3), all without requiring dashboard interaction. missing for 10: independent/hands-on confirmation that MCP or CLI can complete the full create-attach-call flow end-to-end (only vendor docs), and no OpenAPI spec was resolvable (bolna-probe-2) to verify API completeness.

   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”

   proof ↗⚑ flag

2. ai-native userThe platform's own AI helps me author agents — generating or improving prompts, flows, and test cases from a description

   weight 1 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell docs mention a 'Generate from prompt' feature where Conductor drafts an agent from a plain-English description (retell-docs-30), directly supporting AI-assisted agent authoring. However, there's no evidence of AI-driven improvement of existing prompts/flows or automatic test-case generation, and no independent/hands-on confirmation of Conductor's output quality. Missing for 10: documentation on iterative prompt/flow refinement by the platform's AI, automated test-case generation, and community or hands-on verification of Conductor's generated agents.

   • [claimed-docs] “click **Generate from prompt** (marked Suggested) to let [Conductor](/conductor/create-agent) draft an agent from a plain-English descriptio…”
   • [claimed-docs] “Retell agents are node-based flows or single prompts, with call handling, a knowledge base, and integrations built in.”
   • [claimed-docs] “Drag-and-drop, node-based flows for structured, high-stakes calls.”
   • [claimed-docs] “Single prompt agent... Define your whole agent with one prompt.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence shows Bolna's own platform AI generating or improving prompts, flows, or test cases from a description; the closest feature (build-with-ai/mcp) is an MCP server that lets external AI clients like Claude or Cursor manage the account via API, not the platform itself authoring agents. Templates can be cloned, but that's static copying, not AI-generated authoring.

   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [claimed-docs] “Clone any template and customize it for your business.”

   proof ↗⚑ flag

Build

1. developerBuild a working phone voice agent — prompt, voice, and phone number — and take my first live call within an hour

   weight 3 · round drawn
   Retell AI✓fullcommunity8/10

   Docs walk through the exact flow described: create account, pick/generate a template, set prompt and voice, test in dashboard, assign a phone number, and make a live call, with a 15-minute quickstart and free trial credits removing payment friction. Community feedback confirms the demo/agent works end-to-end for real calls, though it also shows occasional conversational glitches (contradictions, confusion) that are quality issues rather than build-flow blockers. missing for 10: independent third-party timing confirmation that a full build-to-first-call truly completes within an hour, and evidence of phone-number provisioning speed in practice.

   • [claimed-docs] “Build your first Retell AI phone agent in 15 minutes: create an account, pick a template, test in the dashboard, deploy to a phone number, a…”
   • [claimed-docs] “Click the "Test" button to start a web call with your agent... This step is free and doesn't need a phone number or payment method.”
   • [claimed-docs] “click **Generate from prompt** (marked Suggested) to let [Conductor](/conductor/create-agent) draft an agent from a plain-English descriptio…”
   • [claimed-docs] “Click the "Test" button to start a web call with your agent”
   • [claimed-docs] “Assign your agent to the number in the configuration settings”
   • [claimed-docs] “New accounts start with \$10 in free trial credits, no payment method required.”
   • [claimed-docs] “Add custom voices to your Retell agent — search ElevenLabs community voices, import a voice clone, or train a clone for a unique brand-speci…”
   • [community] “Curious what model the dentist bot is running on? Tried it out, was surprisingly good, though eventually it contradicted itself (booked a sl…”
   • [community] “I tried to fool the Dental Office demo trying to book on Sunday or outside of the slots it had indicated, and it did a better job than many …”

   proof ↗⚑ flag

   Bolna✓fullclaimed8/10

   Docs directly support the story: templates can be cloned and customized, build/deploy claimed under 5 minutes, voice/accent selection, phone number and telephony setup (BYOT/SIP), and a quickstart walking through key verification, agent creation, placing a call, and fetching a transcript in ~5 minutes. This covers prompt (agent config/templates), voice (voice/provider selection), and phone number (telephony/SIP) end-to-end for a first live call within an hour. Missing for 10: independent/hands-on confirmation of the 'under 5 minutes' or 'first call in an hour' claims beyond vendor docs, and no third-party success report.

   • [claimed-docs] “Build and deploy in under 5 minutes”
   • [claimed-docs] “Clone any template and customize it for your business.”
   • [claimed-docs] “You can choose different voices, accents, and speaking styles to match your brand.”
   • [claimed-docs] “Bring Your Own Telephony (BYOT) lets you connect any standards-compliant SIP trunk to the Bolna platform.”
   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Bolna supports Deepgram, Azure, ElevenLabs, and more.”

   proof ↗⚑ flag

2. developerRun conversations in multiple languages, including detecting and switching language mid-call

   weight 2 · round to Bolna
   Retell AI—none0/10

   No documentation in the evidence pack describes multi-language conversation support, language detection, or mid-call language switching; the only related evidence is a founder comment stating multilingual support is merely 'on our roadmap' rather than shipped, indicating the capability does not currently exist.

   • [community] “Founder said multilingual support is on roadmap: 'It's definitely in our roadmap. After the core product—the voice AI part—becomes humanlike…”

   proof ↗⚑ flag

   Bolna~partialclaimed6/10

   Docs claim the agent "detects and switches mid-call on its own" and marketing mentions "multilingual intelligence" for thousands of calls, directly supporting the story, but there's no detail on supported languages, configuration options, or independent/hands-on verification of mid-call switching reliability. Missing for 10: language list/configuration docs, hands-on or third-party confirmation of switching accuracy, and edge-case handling details.

   • [claimed-docs] “the agent detects and switches mid-call on its own”
   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”

   proof ↗⚑ flag

3. founderDesign multi-step conversation flows in a visual builder with branching, states, and handoffs without writing code

   weight 2 · round to Retell AI
   Retell AI✓fullclaimed7/10

   Retell's docs describe node-based, drag-and-drop conversation flows for 'structured, high-stakes calls' as an alternative to single-prompt agents, with function calling enabling transfers, call-ending, and API calls that serve as handoff points — directly matching the branching/states/handoff story without requiring code. The quick-start flow (pick template, test in dashboard, deploy) reinforces a no-code workflow. Missing for 10: independent/hands-on evidence of the visual builder's branching UI itself (community evidence only covers conversational behavior, not the builder), and no detail on how 'states' are represented/connected beyond the general node-based description.

   • [claimed-docs] “Retell agents are node-based flows or single prompts, with call handling, a knowledge base, and integrations built in.”
   • [claimed-docs] “Drag-and-drop, node-based flows for structured, high-stakes calls.”
   • [claimed-docs] “Single prompt agent... Define your whole agent with one prompt.”
   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”
   • [claimed-docs] “Build your first Retell AI phone agent in 15 minutes: create an account, pick a template, test in the dashboard, deploy to a phone number, a…”
   • [claimed-docs] “click **Generate from prompt** (marked Suggested) to let [Conductor](/conductor/create-agent) draft an agent from a plain-English descriptio…”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence shows Bolna is built around APIs, CLI, and MCP server for defining agents and multi-step outreach sequences (bolna-docs-12, bolna-docs-16, bolna-docs-17), but there is no mention of a visual/no-code builder with branching, states, or handoffs; workflows are described as 'driven entirely through the Bolna API.' Missing for 10: any visual flow-builder UI, drag-and-drop branching/state design, no-code handoff configuration.

   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [github] “Bolna is the end-to-end open source production ready framework for quickly building LLM based voice driven conversational applications.”

   proof ↗⚑ flag

Personalization

1. developerInject dynamic variables and per-caller context at call time so each conversation is personalized

   weight 2 · round drawn
   Retell AI—none0/10

   The evidence pack covers function calling, webhooks, custom telephony, knowledge base retrieval, CRM field sync, and SDK/CLI/MCP tooling, but nowhere describes injecting dynamic variables or per-caller context (e.g., a startCall/create-call parameter for passing caller-specific data into the prompt/LLM at runtime). This is a fair, plausible capability for a voice-agent platform, so absence of evidence yields 'none' rather than 'na'.

   ⚑ flag

   Bolna—none0/10

   The evidence pack covers agent creation, extraction categories, call summaries, workflows, and providers, but nothing documents passing per-caller dynamic variables or context payloads at call time to personalize a conversation.

   ⚑ flag

2. developerGround the agent on my documents with a built-in knowledge base or RAG so it answers from my content

   weight 2 · round to Retell AI
   Retell AI~partialclaimed6/10

   Retell explicitly ships a knowledge base feature where you can crawl websites or upload documents for the agent to retrieve from, and AI QA scores 'knowledge base accuracy' as a call metric, confirming grounding is a first-class capability. However, evidence is thin — only brief homepage-level mentions rather than a dedicated deep-dive doc on KB architecture/RAG internals, and there's no independent/hands-on confirmation of retrieval quality. Missing for 10: dedicated knowledge-base documentation page detailing chunking/retrieval mechanics, and independent verification that answers are accurately grounded in uploaded content.

   • [claimed-docs] “Retell agents are node-based flows or single prompts, with call handling, a knowledge base, and integrations built in.”
   • [claimed-docs] “Crawl a website or upload documents your agent retrieves from.”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”

   proof ↗⚑ flag

   Bolna—none0/10

   Bolna is a voice AI agent platform (telephony, TTS/STT, LLM providers, workflows) but the evidence pack contains no mention of a knowledge base, document ingestion, or RAG capability for grounding agent responses in custom content. This axis clearly applies to conversational agent-building platforms, so absence of evidence yields 'none'.

   ⚑ flag

Agent access

1. ai-native userPoint an agent at llms.txt or agent-oriented docs

   weight 2 · round drawn
   Retell AI✓fullprobed9/10

   A direct probe confirms an llms.txt file exists at docs.retellai.com/llms.txt returning HTTP 200 with a structured index of the docs, and Retell's docs are also agent-oriented enough to support MCP-based discovery/management of resources. This directly satisfies the story of pointing an agent at llms.txt or agent-oriented docs. Missing for 10: no independent third-party corroboration of llms.txt usage in the wild.

   • [probe] “PROBE llms.txt: HTTP 200 at https://docs.retellai.com/llms.txt # Retell AI > Explore Retell AI docs to learn how to build, test, deploy, an…”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”

   proof ↗⚑ flag

   Bolna✓fullprobed9/10

   A probe confirms llms.txt is live and returns 200 with structured agent-oriented doc links (bolna-probe-1), and Bolna also documents an official MCP server for connecting AI clients like Claude/Cursor to its docs/account (bolna-docs-17, bolna-probe-3), directly enabling agent-native consumption of its documentation. Missing for 10: no independent third-party confirmation that agents successfully use llms.txt in practice.

   • [probe] “PROBE llms.txt: HTTP 200 at https://docs.bolna.ai/llms.txt # Bolna Docs > Quickly build and deploy conversational Voice AI agents - [Home]…”
   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”

   proof ↗⚑ flag

2. ai-native userRun the product headlessly / in CI for automation

   weight 2 · round to Retell AI
   Retell AI~partialprobed7/10

   Retell ships official Node.js/Python SDKs with API-key auth and a terminal CLI for managing agents, phone numbers, and resources, both of which are scriptable outside the dashboard, and a runtime probe confirms the CLI installs and runs keylessly via npm — all consistent with headless/CI use. However, there is no explicit CI/automation documentation (e.g., GitHub Actions example, testing-in-pipeline guide) confirming an officially supported headless workflow. Missing for 10: explicit CI/pipeline documentation or example, confirmation of non-interactive auth flow for CI secrets, and independent evidence of real-world CI usage.

   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “The Retell CLI lets you manage Retell resources from your terminal.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “official CLI documented at https://docs.retellai.com/get-started/cli”

   proof ↗⚑ flag

   Bolna~partialprobed6/10

   Bolna offers a CLI (single Go binary) for managing agents, calls, phone numbers, and batches from the terminal, plus a REST API for scripted call creation and transcript retrieval — both usable in CI/automation pipelines without a GUI. However, there's no explicit CI/pipeline example, headless-mode documentation, or exit-code/automation-specific guidance. missing for 10: explicit CI integration examples/guides, documented non-interactive/headless flags or exit codes, third-party confirmation of CI usage.

   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”
   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”

   proof ↗⚑ flag

3. ai-native userPlug MCP servers into this product so it can use their tools

   weight 3 · round to Retell AI
   Retell AI✓fullclaimed8/10

   Retell explicitly documents connecting a live voice/chat agent to a remote MCP server so it can invoke that server's tools during calls, directly matching the story of plugging in external MCP servers for tool use. This is a first-party, well-specified capability (not just Retell exposing its own API as MCP) covering both single- and multi-prompt agents. Missing for 10: independent/hands-on verification that a third-party MCP server's tools work reliably mid-call in production.

   • [claimed-docs] “Connect a Retell single- or multi-prompt agent to a remote MCP server so it can call the server's tools during a live voice or chat conversa…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote Model Context Protocol (MCP) server, and the agent can call that server's tools durin…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote [Model Context Protocol (MCP)] server, and the agent can call that server's tools dur…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence shows Bolna ships an MCP *server* so external clients like Claude, Cursor, or Windsurf can control a Bolna account (bolna-docs-17, bolna-probe-3) — this is the reverse direction from the story, which asks whether Bolna's own agents can plug in external MCP servers to gain their tools. No evidence describes Bolna voice agents consuming or calling external MCP servers.

   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”

   proof ↗⚑ flag

4. ai-native userConnect an agent via an official MCP server

   weight 3 · round to Retell AI
   Retell AI✓fullprobed9/10

   Retell documents and hosts an official MCP server (mcp.retellai.com) that lets MCP-capable clients like Cursor, Claude Desktop, and Claude Code build and manage Retell voice agents via the Retell API, exposing meta-tools for listing/invoking endpoints. A runtime probe confirms the server completes a full keyless JSON-RPC initialize handshake and exposes its tool set, corroborating the vendor docs. Missing for 10: independent/community usage reports of the MCP server in practice beyond vendor docs and the probe.

   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”
   • [claimed-docs] “Retell supports the Model Context Protocol (MCP) so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude D…”
   • [claimed-docs] “Retell supports the [Model Context Protocol (MCP)] so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude…”
   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”
   • [probe] “official MCP server documented at https://docs.retellai.com/get-started/mcp-server”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna✓fullprobed8/10

   Bolna documents an official MCP server that lets Claude, Cursor, Windsurf, or any MCP client connect to a Bolna account, confirmed by both docs and an independent probe hitting the live page. Missing for 10: independent hands-on validation or community confirmation of the MCP server working in practice beyond the docs/probe.

   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”

   proof ↗⚑ flag

5. ai-native userUse an official CLI

   weight 2 · round to Retell AI
   Retell AI✓fullprobed9/10

   Retell ships an official CLI (`@retell-ai/retell-cli`) documented for managing agents, phone numbers, and knowledge bases from the terminal, and a runtime probe confirms it installs and runs keylessly via npx. Missing for 10: independent/community usage reports of the CLI itself (only docs and one probe run corroborate it).

   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “The Retell CLI lets you manage Retell resources from your terminal.”
   • [probe] “official CLI documented at https://docs.retellai.com/get-started/cli”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”

   proof ↗⚑ flag

   Bolna✓fullprobed8/10

   Bolna documents an official CLI (single Go binary) letting users manage agents, calls, phone numbers, and batches from the terminal, corroborated by a live docs probe confirming the page exists. missing for 10: no independent/hands-on community usage reports or version/release history confirming real-world adoption beyond first-party docs.

   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

6. ai-native userDrive the product through a documented public API

   weight 3 · round to Retell AI
   Retell AI✓fullprobed9/10

   Retell documents official Node.js/Python SDKs with typed clients and full endpoint coverage, a CLI for managing resources from the terminal, and API references (e.g., clone-voice endpoint) — and a runtime probe confirms the CLI installs/runs keylessly and the hosted MCP server exposes the entire API via meta-tools, proving the API is genuinely agent-drivable. Missing for 10: a publicly discoverable OpenAPI/swagger spec (all standard paths returned 404 in the probe).

   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [claimed-docs] “Type safety: Full TypeScript support with autocomplete ... Error handling: Structured error responses with detailed messages”
   • [probe] “official MCP server documented at https://docs.retellai.com/get-started/mcp-server”
   • [probe] “official CLI documented at https://docs.retellai.com/get-started/cli”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.retellai.com/openapi.json, https://docs.retellai.com/swagger.json, https://docs.retella…”

   proof ↗⚑ flag

   Bolna✓fullprobed8/10

   Bolna provides a documented public API with quickstart, authentication, agent/call/extraction endpoints, and workflow automation entirely through the API, plus a CLI and MCP server built on top of it. Missing for 10: a discoverable OpenAPI/Swagger spec (probe found all standard OpenAPI paths 404) and independent third-party corroboration of API robustness.

   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”
   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

7. ai-native userIssue scoped/least-privilege API credentials for an agent

   weight 2 · round drawn
   Retell AI—none0/10

   The evidence pack documents API key auth, SDKs, CLI, and an MCP server, but nowhere describes scoped, role-based, or least-privilege API key/credential issuance (e.g., per-agent or per-permission keys) for Retell. This is a fair axis for an API/voice-agent platform, but no docs or probes show scoped credential support, so it is unproven.

   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”

   proof ↗⚑ flag

   Bolna—none0/10

   Bolna documents API key creation but there is no evidence of scoped or least-privilege credential controls (e.g., role-based permissions, scoped tokens, restricted access levels) — only a single account-wide key generation flow is described.

   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”

   proof ↗⚑ flag

8. ai-native userBuild against official SDKs

   weight 2 · round to Retell AI
   Retell AI✓fullprobed9/10

   Retell documents and ships official typed SDKs for Node.js and Python with API key auth, full endpoint coverage, structured errors, and TypeScript autocomplete, plus an official CLI and MCP server for programmatic/agentic access — all independently confirmed by runtime probes (CLI installs and runs, MCP server completes handshake). Missing for 10: no independent third-party review of SDK quality/DX beyond vendor docs and no public OpenAPI spec discovered.

   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [claimed-docs] “Type safety: Full TypeScript support with autocomplete ... Error handling: Structured error responses with detailed messages”
   • [probe] “official CLI documented at https://docs.retellai.com/get-started/cli”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “official MCP server documented at https://docs.retellai.com/get-started/mcp-server”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna~partialprobed5/10

   Bolna documents an official Web Call SDK (bolna-docs-18) under a 'developer-resources/sdks' path, plus a CLI and MCP server, giving AI-native builders some official tooling to build against, but there is no evidence of broader language SDKs (e.g., Python, Node, Go client libraries) beyond the browser-based Web Call SDK. missing for 10: multi-language server-side SDKs, independent/hands-on verification of SDK usability, breadth beyond the single web-call SDK.

   • [claimed-docs] “The Web Call SDK connects a browser tab directly to a Bolna voice agent for a live, two-way conversation.”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”
   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”

   proof ↗⚑ flag

9. ai-native userSubscribe to events via webhooks

   weight 2 · round to Retell AI
   Retell AI✓fullclaimed8/10

   Retell has dedicated first-party documentation for webhooks describing real-time event notifications pushed to your application as events occur, enabling event-driven integrations rather than polling — directly matching the story of subscribing to events via webhooks. Missing for 10: no independent/hands-on corroboration of webhook reliability or event catalog completeness beyond the docs themselves.

   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence in the pack mentions webhooks or event subscription for Bolna; the docs cover agents, calls, CLI, MCP, SIP, pricing, and security but nothing about outbound event notifications. Missing for 10: any webhook registration/config API, event payload documentation, or third-party confirmation of webhook delivery.

   ⚑ flag

Agentic features

1. ai-native userGet AI-generated insights and suggestions from my data inside the product

   weight 2 · round to Retell AI
   Retell AI~partialclaimed6/10

   Retell's AI QA feature automatically scores calls on hallucination, knowledge-base accuracy, latency, sentiment, and tool usage to surface quality trends and issues, and custom analytics dashboards let users chart/filter call and chat metrics — both are AI-derived insights from the product's own call data. However, this is scoring/quality analytics rather than proactive generative 'suggestions' (e.g., recommended actions, next-best-response, or coaching tips), and there's no independent/hands-on evidence validating the accuracy or usefulness of these AI-generated insights. Missing for 10: evidence of proactive suggestion/recommendation generation beyond scoring, and third-party corroboration of AI QA insight quality.

   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “Built-in call success and sentiment scoring, plus custom fields synced to your CRM.”

   proof ↗⚑ flag

   Bolna~partialclaimed5/10

   Bolna offers agent-level call_summary_enabled to auto-generate AI summaries and an extraction-categories API to pull structured insights out of call data, both of which are AI-generated insights derived from user data (calls). However, there's no evidence of broader cross-call analytics, trend insights, or proactive suggestions surfaced in a dashboard beyond per-call outputs. Missing for 10: aggregated/dashboard-level insights across multiple calls, proactive recommendation surfacing, and independent confirmation of quality of generated summaries/extractions.

   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”

   proof ↗⚑ flag

2. ai-native userSet up automations that run autonomously in the background

   weight 2 · round drawn
   Retell AI~partialcommunity6/10

   Retell agents act autonomously during live calls — function calling lets them independently book appointments, send SMS, transfer calls, and call external APIs without human intervention (retell-docs-5, retell-docs-35), and webhooks push real-time events to downstream systems (retell-docs-12, retell-docs-24). This shows in-call autonomous action-taking, which is a form of background automation once a call is triggered. However, there's no evidence of standalone scheduled/triggered automations running independent of a live voice/chat session (e.g., cron-like outbound campaigns or autonomous multi-step workflows outside conversation context). Missing for 10: evidence of scheduled or event-triggered background automations outside live calls, and independent/hands-on confirmation that autonomous function-calling reliably completes tasks unattended (community reports show some confusion/looping during autonomous task execution, retell-comm-1, retell-comm-3, retell-comm-5).

   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”
   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”
   • [community] “The AI contradicted itself when layering conditionals - it got confused about morning vs afternoon time, kept asking to repeat despite corre…”
   • [community] “Voice sounds great, but: told it unavailable until next year, it confirmed Feb 4th 'next year' but thought current year was 2022. Also got s…”

   proof ↗⚑ flag

   Bolna~partialprobed6/10

   Bolna's workflows feature lets users build multi-step outreach sequences (voice calls, WhatsApp, API calls, waits, retries) driven entirely through the API, which supports background automation, and the CLI can manage batches of calls autonomously. However there's no documented evidence of scheduling/triggers, monitoring/alerting on autonomous runs, or a dashboard for managing long-running background jobs beyond the API-driven workflow primitives. missing for 10: scheduling/trigger mechanisms, autonomous-run monitoring/alerting, independent hands-on confirmation of unattended long-running workflows.

   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

3. ai-native userDelegate tasks to a built-in AI assistant inside the product

   weight 3 · round to Retell AI
   Retell AI~partialclaimed3/10

   Retell's dashboard includes 'Conductor', a built-in AI assistant that can draft an entire agent from a plain-English prompt (docs-30), which is a genuine instance of delegating a task to an in-product AI assistant. However this is a single thin mention with no further detail on scope, limits, or other delegable tasks beyond initial agent creation. Missing for 10: documentation of Conductor's full capabilities/limits, evidence of delegating other tasks (not just agent drafting) to a built-in assistant, and independent/hands-on corroboration of Conductor actually working.

   • [claimed-docs] “click **Generate from prompt** (marked Suggested) to let [Conductor](/conductor/create-agent) draft an agent from a plain-English descriptio…”

   proof ↗⚑ flag

   Bolna—none0/10

   The axis applies to this product kind (peer products hold positive or none verdicts on this story), so lack of evidence for an applicable capability is "none", never "na". (na/none harmonized at arena bring-up — see pipeline/scripts/na-harmonize.ts.)

   ⚑ flag

4. ai-native userOperate the product with natural-language commands

   weight 2 · round drawn
   Retell AI✓fullprobed7/10

   Retell supports natural-language operation via Conductor's 'Generate from prompt' feature that drafts an agent from a plain-English description, and via its official MCP server which exposes the full API as agent-callable tools so AI-native clients (Cursor, Claude Desktop, Claude Code) can build/manage agents through natural-language MCP tool calls — confirmed live by a keyless JSON-RPC probe against the hosted MCP endpoint. missing for 10: independent/hands-on evaluation of Conductor's prompt-to-agent quality, and no evidence of NL commands for other everyday operations (e.g., dashboard chat-based control) beyond agent creation/management.

   • [claimed-docs] “click **Generate from prompt** (marked Suggested) to let [Conductor](/conductor/create-agent) draft an agent from a plain-English descriptio…”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”
   • [claimed-docs] “Retell supports the Model Context Protocol (MCP) so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude D…”
   • [claimed-docs] “Retell supports the [Model Context Protocol (MCP)] so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude…”
   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”
   • [probe] “official MCP server documented at https://docs.retellai.com/get-started/mcp-server”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna✓fullprobed7/10

   Bolna ships an official MCP server that lets AI-native tools like Claude, Cursor, or Windsurf connect to a Bolna account and operate it (manage agents, calls, etc.) via natural-language commands, confirmed both in docs and via a live probe. Missing for 10: independent/hands-on verification that the MCP integration works as described, and no additional natural-language control surfaces (e.g., chat-based dashboard) beyond MCP.

   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”

   proof ↗⚑ flag

Api quality

1. ai-native userExplore an interactive API reference with runnable examples

   weight 2 · round drawn
   Retell AI—none0/10

   Evidence shows Retell has API reference doc pages (e.g., api-references/clone-voice.md) and SDKs/CLI/MCP tooling, but no evidence of an interactive, runnable API reference (e.g., embedded 'try it' console or Swagger UI). The probe explicitly found no OpenAPI/Swagger spec exposed (all candidate paths 404), undermining any claim of an interactive reference.

   • [claimed-docs] “Clone a voice from audio files”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.retellai.com/openapi.json, https://docs.retellai.com/swagger.json, https://docs.retella…”

   proof ↗⚑ flag

   Bolna—none0/10

   Bolna has an API reference doc listing basics like API key creation, but there is no evidence of an interactive reference with runnable/try-it examples, and a probe for a machine-readable OpenAPI spec (which typically powers such interactive docs) returned 404 on all checked paths.

   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”

   proof ↗⚑ flag

2. ai-native userDownload a machine-readable API spec (OpenAPI or equivalent)

   weight 2 · round drawn
   Retell AI—none0/10

   A direct probe for standard OpenAPI/Swagger spec locations (openapi.json, swagger.json, etc.) on Retell's docs domain returned 404 for all candidates, and no evidence pack item shows a downloadable, machine-readable API spec being published or linked from docs. The CLI's version string mentions an internal 'OpenAPI 3.0.0' schema, but this is not shown to be an artifact users can download or fetch programmatically.

   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.retellai.com/openapi.json, https://docs.retellai.com/swagger.json, https://docs.retella…”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”

   proof ↗⚑ flag

   Bolna—none0/10

   A direct probe for OpenAPI/Swagger spec files at all standard locations returned 404s, and no evidence pack item shows a downloadable machine-readable API spec despite having an API reference page.

   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”
   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”

   proof ↗⚑ flag

3. ai-native userTest against a sandbox environment without touching production data

   weight 1 · round to Retell AI
   Retell AI~partialclaimed4/10

   Retell's quick-start lets you click 'Test' to run a free web call with your agent before it ever touches a phone number or payment method, and new accounts get $10 trial credit to experiment risk-free — a lightweight way to try an agent without production telephony traffic. However, there's no documented dedicated sandbox environment, test-mode API flag, or explicit data isolation guarantee separating test calls from production records/analytics. Missing for 10: explicit sandbox/staging environment concept, test vs prod data isolation guarantees, and independent confirmation that test-call data doesn't mix with production analytics/QA.

   • [claimed-docs] “Click the "Test" button to start a web call with your agent... This step is free and doesn't need a phone number or payment method.”
   • [claimed-docs] “Click the "Test" button to start a web call with your agent”
   • [claimed-docs] “New accounts start with \$10 in free trial credits, no payment method required.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence pack item mentions a sandbox environment, test mode, staging account, or separation from production data for Bolna; the closest concepts (self-hosting, BYOK, data residency) are about deployment/privacy, not a distinct sandbox/test mode. missing for 10: any mention of a sandbox/test environment, test API keys, or safe testing workflow that avoids production data.

   ⚑ flag

4. ai-native userRely on versioned APIs with a documented deprecation policy

   weight 2 · round drawn
   Retell AI—none0/10

   The evidence pack covers SDKs, CLI, MCP server, and API endpoints extensively, but there is no documentation of API versioning scheme or a deprecation policy for breaking changes. The probe notes an OpenAPI version string (3.0.0, catalog v4) but this is not evidence of a documented deprecation/versioning policy for API consumers.

   ⚑ flag

   Bolna—none0/10

   There is a changelog page referenced and an API reference, but no evidence of API versioning scheme or a documented deprecation policy anywhere in the pack; OpenAPI spec probes even returned 404s. Missing for 10: versioned API endpoints/headers, explicit deprecation policy documentation, migration/versioning changelog entries.

   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”
   • [claimed-docs] “Click the Create a new API Key button to generate your unique authentication credentials.”

   proof ↗⚑ flag

1. ai-native userPerform bulk operations across many items at once

   weight 2 · round to Bolna
   Retell AI~partialprobed4/10

   Retell exposes a full-coverage SDK, CLI, and MCP server that let an AI agent script repeated single-item operations (create/update/list agents, phone numbers, knowledge bases) programmatically, enabling scripted bulk-like loops, but there is no documented native batch/bulk endpoint operating on many items in a single call. missing for 10: explicit batch/bulk API endpoints or CLI commands operating on multiple items in one call, evidence of rate-limit-safe bulk workflows, and hands-on confirmation of bulk usage at scale

   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”

   proof ↗⚑ flag

   Bolna~partialclaimed5/10

   The CLI explicitly manages 'batches' of calls alongside agents and phone numbers (bolna-docs-16), and the platform claims to power 'thousands of inbound and outbound calls every minute' (bolna-docs-22), implying built-in bulk calling capability. However, there is no documentation of a specific bulk API endpoint, CSV/list upload, or bulk agent/category management workflow. Missing for 10: explicit bulk-operation API docs (e.g., batch call creation, bulk agent updates), a documented interface for uploading many items at once, and independent confirmation of bulk throughput.

   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”
   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”

   proof ↗⚑ flag

2. ai-native userDefine rules that trigger actions automatically on events

   weight 3 · round to Retell AI
   Retell AI~partialclaimed6/10

   Retell supports event-driven automation via webhooks that fire on account events (retell-docs-12, retell-docs-24), function calling that lets agents automatically transfer calls, end calls, book appointments, or call external APIs based on conversation logic (retell-docs-5, retell-docs-35), and node-based flows with conditional branching (retell-docs-25) plus AI QA rules evaluated against configured metrics (retell-docs-43). However, this is scattered across call-flow logic and webhook notifications rather than a unified 'if event then action' rule-definition interface. Missing for 10: a dedicated rules/trigger engine UI for arbitrary account-wide events, documentation of webhook-to-action automation chains, and independent verification that rule-based automation works reliably (community reports note conversational logic errors, e.g. retell-comm-1, retell-comm-3, retell-comm-7).

   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”
   • [claimed-docs] “Drag-and-drop, node-based flows for structured, high-stakes calls.”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”

   proof ↗⚑ flag

   Bolna~partialclaimed4/10

   Bolna's workflow feature lets users chain voice calls, WhatsApp messages, API calls, waits and retries via the API, which is a form of automation, but the docs never describe defining conditional 'if event X happens then do Y' rules or an event/trigger system — it's presented as sequential outreach flows rather than rule-based event triggers. Missing for 10: explicit event-trigger/rule definition syntax, conditional branching logic, and any webhook-or-event-driven automation examples beyond the sequential workflow description.

   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”

   proof ↗⚑ flag

3. ai-native userSchedule recurring jobs or workflows

   weight 2 · round drawn
   Retell AI—none0/10

   Retell's docs cover webhooks, function calling, MCP tool-calling, and telephony integration, but nothing describes scheduling recurring jobs, campaigns, or workflows (e.g., cron-like recurring outbound call batches or repeating automations). This is a fair question for a voice-agent platform (buyers often want scheduled/recurring outbound campaigns), so the axis applies, but no evidence in the pack shows this capability. missing for 10: any mention of a scheduler, recurring campaign/job feature, or cron-style automation trigger.

   ⚑ flag

   Bolna—none0/10

   Bolna's workflow docs describe multi-step outreach sequences with waits and retries (bolna-docs-12), but there is no evidence of a scheduler for recurring/cron-based jobs or workflows that re-trigger automatically over time. missing for 10: recurring/scheduled trigger mechanism, cron-like job definitions, evidence of periodic re-execution.

   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”

   proof ↗⚑ flag

4. ai-native userVersion, review, and roll back my automations

   weight 1 · round to Retell AI
   Retell AI~partialclaimed4/10

   Retell supports 'agent versions' with create/update/publish/list/fetch operations via CLI and MCP (retell-docs-47), implying some versioning and possibly rollback via republishing an older version, but there is no documented review workflow (diffs, approvals, changelogs) or explicit rollback command/UI. missing for 10: explicit rollback mechanism, version diff/review UI, changelog or audit trail, and any independent/hands-on confirmation that version history and rollback actually work as described.

   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”

   proof ↗⚑ flag

   Bolna—none0/10

   Bolna is a voice AI agent platform (agent creation, calls, workflows, telephony) but the evidence pack shows no version control, review workflow, or rollback mechanism for automations/agents — no mention of agent versioning, change history, approval flows, or revert capability.

   ⚑ flag

Compliance

1. founderMeet call-recording consent and disclosure obligations with per-call recording controls and configurable data retention

   weight 2 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell documents per-agent configurable data retention that auto-deletes transcripts, recordings, and logs after a set period, directly addressing retention obligations. However, there is no evidence of explicit per-call recording enable/disable controls or built-in consent-disclosure features (e.g., automated recording announcements) that founders would need for two-party consent compliance. Missing for 10: per-call recording on/off toggle, consent-disclosure/announcement mechanism, and any documentation tying these to legal consent requirements.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”

   proof ↗⚑ flag

   Bolna—none0/10

   The evidence pack shows security/data-residency features and call-summary toggles, but nothing about call-recording consent, per-call recording enable/disable controls, disclosure/announcement features, or configurable retention periods for recordings/transcripts. No mention of recording consent mechanisms or retention settings anywhere in the docs pack.

   ⚑ flag

2. platform-engineerRun regulated workloads with HIPAA/BAA support, SOC 2, and data-residency options

   weight 2 · round to Bolna
   Retell AI—none0/10

   Evidence shows only generic data-retention controls (docs-15/27/44) but no mention of HIPAA, BAA, SOC 2 certification, or data-residency options anywhere in the docs or community pack, despite this being a fair compliance axis for a voice-AI platform handling call recordings/transcripts.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”

   proof ↗⚑ flag

   Bolna~partialclaimed3/10

   Bolna documents Indian data residency and self-hosting via Docker/Kubernetes for private enterprise deployments, but there is no mention of HIPAA/BAA support or SOC 2 certification anywhere in the evidence pack. missing for 10: HIPAA/BAA attestation, SOC 2 report or certification, broader multi-region data-residency options beyond India.

   • [claimed-docs] “Indian data residency is available for deployments where data must remain in India.”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

Scale

1. platform-engineerSee documented concurrency limits and scale to many simultaneous calls without manual capacity begging

   weight 2 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell documents a concurrency configuration feature (reserved inbound concurrency vs. outbound limit) showing platform-level concurrency controls exist, but there is no documented default/numeric concurrency limits per plan, no described self-service process to raise limits without contacting support, and no evidence (docs or community) confirming scaling to many simultaneous calls happens without manual requests. missing for 10: published default concurrency limits, self-service limit-increase mechanism, and independent confirmation of large-scale concurrent call handling without support intervention.

   • [claimed-docs] “Reserved inbound concurrency protects inbound calls from being crowded out by outbound traffic.”
   • [claimed-docs] “When `reserved_inbound_concurrency` is configured, outbound calls can use at most your concurrency limit minus the reserved amount.”

   proof ↗⚑ flag

   Bolna~partialclaimed3/10

   Bolna's marketing page claims it can 'power thousands of inbound and outbound calls every minute' and docs mention self-hosting via Docker/Kubernetes for 'scalable enterprise deployments,' but there are no documented concurrency limits, rate-limit tables, or self-serve capacity-scaling mechanisms (e.g., no API rate-limit docs, no autoscaling guide, no numeric SLA). missing for 10: documented numeric concurrency/rate limits, self-serve scale-up process, autoscaling architecture details, independent verification of claimed call volume.

   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

Self host

1. platform-engineerSelf-host the voice agent runtime from open-source code on my own infrastructure

   weight 3 · round to Bolna
   Retell AI—none0/10

   Retell AI is a hosted SaaS voice-agent platform; all evidence points to cloud-hosted APIs, SDKs, CLI, and MCP server that call Retell's own servers, with no mention of open-source runtime code or self-hosting instructions. There is no evidence a platform-engineer can download and run the voice agent runtime on their own infrastructure.

   • [claimed-docs] “Build your first Retell AI phone agent in 15 minutes: create an account, pick a template, test in the dashboard, deploy to a phone number, a…”
   • [claimed-docs] “Retell starts at $0, pay only for what you use.”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna✓fullclaimed8/10

   Bolna is explicitly an open-source framework on GitHub, and docs include dedicated enterprise instructions for self-hosting on Docker or Kubernetes for private/enterprise deployments. Missing for 10: independent hands-on reports confirming successful self-host deployment and more detail on infrastructure requirements/limitations of the self-hosted version vs SaaS.

   • [github] “Bolna is the end-to-end open source production ready framework for quickly building LLM based voice driven conversational applications.”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

Latency

1. platform-engineerSee documented end-to-end voice latency numbers or tuning guidance backing the platform's speed claims

   weight 3 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell docs offer tuning guidance for latency (transcription mode trade-offs, endpointing settings) and let customers monitor latency via analytics dashboards and AI QA scoring, but there are no documented end-to-end latency benchmarks or numbers substantiating speed claims. missing for 10: published end-to-end latency figures/benchmarks, and independent verification of speed claims.

   • [claimed-docs] “Pick the right Retell transcription mode to balance accuracy against latency — interim results for speed or context-aware results for higher…”
   • [claimed-docs] “Real time transcription is often a trade off between latency and accuracy.”
   • [claimed-docs] “optimize for speed: uses the latest interim results with a low endpointing setting... optimize for accuracy: uses the results with a higher …”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence pack item provides documented latency numbers, benchmarks, or tuning guidance for end-to-end voice latency; only vague marketing claims like 'build in under 5 minutes' or 'power thousands of calls' appear, with no actual latency figures or turn-taking tuning documentation.

   • [claimed-docs] “Build and deploy in under 5 minutes”
   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”

   proof ↗⚑ flag

Turn taking

1. developerRely on the agent to handle interruptions (barge-in) gracefully — stopping speech, updating context, and recovering the turn

   weight 3 · round drawn
   Retell AI—none0/10

   The evidence pack covers transcription latency/accuracy trade-offs (retell-docs-9, retell-docs-39, retell-docs-48) but nowhere describes explicit barge-in/interruption handling — stopping agent speech, updating context, and recovering the turn when a caller interrupts. Community threads show turn-taking confusion (contradictions, loops, disconnects) but do not address interruption handling specifically. Missing for full/partial credit: any documentation or hands-on report confirming barge-in detection, speech-stop behavior, or turn recovery mechanics.

   ⚑ flag

   Bolna—none0/10

   No evidence pack item mentions barge-in, interruption handling, speech-stop, or turn recovery mechanics; the docs cover extraction categories, summaries, providers, CLI, MCP, pricing, etc., but nothing about turn-taking or interruption behavior. missing for 10: any documentation of barge-in/interruption detection, mid-speech stop mechanics, context update on interruption, turn recovery logic.

   ⚑ flag

2. developerEnable noise suppression or audio filtering so the agent stays coherent on noisy real-world calls

   weight 1 · round drawn
   Retell AI—none0/10

   No evidence pack item mentions noise suppression, background-noise filtering, or audio-preprocessing features for handling noisy real-world call environments; the closest related feature (transcription-mode trade-off between latency and accuracy) addresses turn-taking speed, not noise robustness. This is a plausible axis for a voice-agent platform, so absence of evidence yields 'none' rather than 'na'.

   ⚑ flag

   Bolna—none0/10

   No evidence pack item mentions noise suppression, background noise handling, or audio filtering settings for calls; the docs cover extraction categories, summaries, telephony, SDKs, and pricing but not audio quality/noise robustness features. Missing for 10: any mention of noise suppression/audio filtering configuration, VAD tuning for noisy environments, or documented handling of real-world call noise.

   ⚑ flag

3. developerUse model-based end-of-turn detection beyond simple VAD silence timeouts so the agent doesn't talk over slow speakers

   weight 2 · round drawn
   Retell AI—none0/10

   The transcription-mode docs only describe tuning an 'endpointing setting' (low vs high) as a speed/accuracy tradeoff for VAD-style silence detection, not a distinct model-based semantic end-of-turn detector that understands incomplete utterances from slow speakers. No evidence pack item describes a dedicated turn-detection model or algorithm beyond adjusting silence-timeout thresholds.

   • [claimed-docs] “Pick the right Retell transcription mode to balance accuracy against latency — interim results for speed or context-aware results for higher…”
   • [claimed-docs] “Real time transcription is often a trade off between latency and accuracy.”
   • [claimed-docs] “optimize for speed: uses the latest interim results with a low endpointing setting... optimize for accuracy: uses the results with a higher …”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence describes model-based end-of-turn/turn-taking detection distinct from VAD silence timeouts; evidence only covers mid-call model switching, extraction categories, and unrelated features. Missing for 10: any mention of endpointing model, semantic turn detection, or configurable end-of-turn logic beyond silence thresholds.

   ⚑ flag

1. ai-native userDo everything through the API that I can do in the UI

   weight 2 · round to Retell AI
   Retell AI✓fullprobed8/10

   Retell exposes full API coverage via official Node/Python SDKs, a CLI, and a hosted MCP server that dynamically exposes the entire API (list/get/invoke endpoint tools), confirmed by keyless runtime probes actually reaching the CLI and MCP handshake — meaning nearly anything doable in the dashboard (agents, phone numbers, knowledge bases, function calling, voice cloning, analytics) is API/CLI/MCP accessible. missing for 10: no public OpenAPI spec was found (404s across candidate paths), and no independent hands-on confirmation that every single UI feature (e.g., analytics dashboards, AI QA config) has a 1:1 API equivalent.

   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Use Retell's MCP server to build and manage voice agents from MCP-capable clients like Cursor, Claude Desktop, and Claude Code via Retell AP…”
   • [claimed-docs] “Retell supports the Model Context Protocol (MCP) so you can build Retell AI voice agents directly from MCP-capable clients (Cursor, Claude D…”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.retellai.com/openapi.json, https://docs.retellai.com/swagger.json, https://docs.retella…”
   • [claimed-docs] “Agents: create, update, publish, list, and fetch agent versions.”

   proof ↗⚑ flag

   Bolna~partialprobed7/10

   Docs show the platform is API-first — agent creation, extraction categories, call summaries, workflows, and telephony are all described as configurable via the API, and a CLI and MCP server both wrap that same API, implying broad parity. However, there is no explicit documentation stating full UI/API feature parity, and probes found no discoverable OpenAPI/swagger spec (404s), leaving some doubt about completeness of coverage for every UI action. Missing for 10: explicit UI-API parity statement, published OpenAPI/swagger spec, independent confirmation that all UI actions have API equivalents.

   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”
   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “PROBE openapi: all candidate paths 404 (https://docs.bolna.ai/openapi.json, https://docs.bolna.ai/swagger.json, https://docs.bolna.ai/api/op…”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

2. ai-native userExport all of my data in open formats and leave

   weight 3 · round to Bolna
   Retell AI—none0/10

   Docs describe API/SDK/CLI access, data retention (auto-deletion) and analytics dashboards, but nowhere document a data-export or portability feature that would let a user pull all call/chat data, transcripts, and recordings in an open format to leave the platform; retention docs only cover automatic deletion, not export.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”

   proof ↗⚑ flag

   Bolna~partialclaimed3/10

   Bolna's API lets you fetch call transcripts (bolna-docs-14) and the platform can be self-hosted via Docker/Kubernetes (bolna-docs-9), with an open-source core framework (bolna-gh-1), which together provide some data portability, but there is no documented bulk 'export all data' feature or guarantee of open, standard export formats covering call recordings, agent configs, analytics, etc. Missing for 10: an explicit full-data export tool/endpoint, documented open format specification for exported data, and independent confirmation that a user can fully migrate away with all their data.

   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”
   • [github] “Bolna is the end-to-end open source production ready framework for quickly building LLM based voice driven conversational applications.”

   proof ↗⚑ flag

3. ai-native userRead the product's source under an open license

   weight 2 · round to Bolna
   Retell AI—none0/10

   Retell AI is a closed, proprietary SaaS platform; the evidence pack shows SDKs, CLI, MCP server and docs but no mention of source code being published under any open license, nor any GitHub repo for the core platform. Missing for 10: any open-source license grant, public source repository, or licensing terms for the core agent/voice engine.

   ⚑ flag

   Bolna~partialclaimed5/10

   The GitHub repo description explicitly calls Bolna 'the end-to-end open source production ready framework,' supporting that its source is publicly available under an open-license framing, but no specific license (e.g., MIT/Apache) is named or verified, and no independent corroboration exists. Missing for 10: explicit license identification (e.g., LICENSE file contents), confirmation the entire product (not just the framework) is open-sourced, and independent verification.

   • [github] “Bolna is the end-to-end open source production ready framework for quickly building LLM based voice driven conversational applications.”

   proof ↗⚑ flag

4. ai-native userSelf-host the core product

   weight 3 · round to Bolna
   Retell AI—none0/10

   Retell AI is presented entirely as a hosted SaaS (cloud dashboard, hosted APIs, hosted MCP server, usage-based pricing) with no mention anywhere in docs of a self-hosted or on-prem deployment option; all evidence points to a fully managed cloud product.

   • [claimed-docs] “Retell starts at $0, pay only for what you use.”
   • [claimed-docs] “Build your first Retell AI phone agent in 15 minutes: create an account, pick a template, test in the dashboard, deploy to a phone number, a…”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”
   • [claimed-docs] “Integrate Retell voice agents with your own telephony provider using elastic SIP trunking or imported numbers from Twilio, Telnyx, and Vonag…”

   proof ↗⚑ flag

   Bolna✓fullclaimed8/10

   Bolna is explicitly open source (GitHub repo) and documentation provides dedicated on-premise instructions for self-hosting via Docker or Kubernetes for enterprise deployments, directly satisfying the self-host story. Missing for 10: independent/hands-on confirmation of a successful self-hosted deployment and more detail on feature parity between self-hosted and cloud versions.

   • [github] “Bolna is the end-to-end open source production ready framework for quickly building LLM based voice driven conversational applications.”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

Pricing

1. founderSee published per-minute or usage pricing and estimate cost per call before committing

   weight 2 · round to Retell AI
   Retell AI✓fullcommunity8/10

   Retell's pricing page explicitly states pay-as-you-go pricing starting at $0 with no annual contracts, offers an interactive calculator to estimate approximate monthly cost by adjusting key parameters, and new accounts get $10 free trial credit to test before paying — directly enabling a founder to estimate call costs before committing. Community discussion also confirms a concrete per-minute rate (17¢/min) is being charged in practice, corroborating usage-based billing exists. missing for 10: the per-minute rate itself is not shown in first-party docs (only inferred from a community comment), and there's no independent verification of the calculator's accuracy.

   • [claimed-docs] “Retell starts at $0, pay only for what you use.”
   • [claimed-docs] “Adjust key parameters to see an approximate monthly cost for your Retell AI voice agents.”
   • [claimed-docs] “Most voice AI platforms require annual contracts before you write a single line of code. Retell starts at $0, pay only for what you use.”
   • [claimed-docs] “New accounts start with \$10 in free trial credits, no payment method required.”
   • [community] “Founder (yanyan_evie) noted voice provider costs differ: 'The different providers have different prices. openai tts & deepgram are cheaper, …”
   • [community] “A commenter noted per-minute pricing (17¢/min) could be exploited: a malicious caller could keep the bot on the line for hours across many p…”

   proof ↗⚑ flag

   Bolna~partialclaimed4/10

   There is a dedicated call-pricing doc page and mentions that BYOK/connected providers aren't charged (bolna-docs-19, bolna-docs-10), indicating some usage-based pricing structure exists, but no evidence pack item actually quotes a per-minute rate, tiered pricing table, or a cost calculator a founder could use to estimate cost per call. Missing for 10: explicit per-minute/usage rate figures, a pricing calculator or worked cost example, and independent confirmation that published rates are accurate.

   • [claimed-docs] “When you bring your own keys (BYOK), Bolna does not charge for those components.”
   • [claimed-docs] “We don't charge for any usage for providers that you have connected to Bolna.”

   proof ↗⚑ flag

1. ai-native userChoose where my data is stored (region/residency)

   weight 2 · round to Bolna
   Retell AI—none0/10

   No evidence in the pack mentions data residency, region selection, or geographic storage options; the closest related feature is per-agent data retention/deletion (retell-docs-15/27/44), which addresses retention duration, not location of storage. This axis is applicable to a cloud AI voice platform handling call/chat data, so absence of evidence yields 'none'. Missing for 10: any documentation of selectable regions, data residency guarantees, or geo-specific hosting.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”

   proof ↗⚑ flag

   Bolna~partialclaimed6/10

   Docs explicitly mention Indian data residency as an available option, and self-hosting via Docker/Kubernetes lets enterprises control where data lives entirely. However, there's no broader multi-region selection (e.g., EU, US) documented beyond India, and no detail on how residency is configured or enforced. Missing for 10: documented multi-region choice beyond India, configuration/UI for selecting region, and independent confirmation of residency enforcement.

   • [claimed-docs] “Indian data residency is available for deployments where data must remain in India.”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

2. ai-native userPrevent my data from being used to train AI models

   weight 3 · round drawn
   Retell AI—none0/10

   The evidence only covers configurable data retention (auto-deleting transcripts/recordings/logs after a set period) for compliance, not an explicit opt-out or guarantee against using customer data for AI model training. No docs mention training-data usage policy, opt-out toggles, or contractual no-train clauses.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence pack item addresses a training-data opt-out or policy on AI model training use; security docs cover data residency and IP whitelisting only, not training-data usage controls. missing for 10: any explicit statement on AI training data usage/opt-out policy, data processing agreement terms, or contractual guarantee against training use.

   ⚑ flag

3. ai-native userControl data retention and deletion

   weight 2 · round to Retell AI
   Retell AI!disputedcontradicted5/10

   Retell's docs describe per-agent configurable data retention with automatic, permanent deletion of call/chat transcripts, recordings, and logs after a set period (retell-docs-15, retell-docs-27, retell-docs-44), which is solid first-party evidence for the retention-control axis. However, an independent community report describes the company refusing to delete a user's stored data (credit card) on request, forcing the user to escalate to bank disputes/consumer-affairs complaints — a concrete real-world case where deletion did not work as a customer expected (retell-comm-14). Missing for 10: independent verification that call/chat data deletion itself (not just billing data) works as documented, and no public response/resolution to the deletion complaint.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”
   • [community] “Thread titled 'Retellai won't delete my credit card' - a user complained the company would not delete their stored credit card; commenters s…”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence of data retention controls, deletion APIs, or user-facing privacy/data-lifecycle settings; only tangential mentions of security (IP whitelisting, India data residency) which do not address retention/deletion. Self-hosting option exists but that's deployment control, not a retention/deletion feature.

   • [claimed-docs] “Indian data residency is available for deployments where data must remain in India.”
   • [claimed-docs] “Whitelist all three IPs on your server or firewall”
   • [claimed-docs] “Learn how to self-host Bolna Voice AI on your own servers using Docker or Kubernetes for secure, private, and scalable enterprise deployment…”

   proof ↗⚑ flag

4. ai-native userOpt out of telemetry and usage tracking

   weight 2 · round drawn
   Retell AI—none0/10

   The evidence pack covers data retention for call/chat data (transcripts, recordings, logs) but contains no mention of telemetry or usage-tracking opt-out controls for the product itself (e.g., CLI/SDK/dashboard analytics collection). Data retention (retell-docs-15/27/44) addresses deletion of customer call data, not opting out of Retell's own telemetry collection.

   ⚑ flag

   Bolna—none0/10

   No evidence pack item addresses telemetry, analytics opt-out, or usage-tracking controls for the platform itself; existing security/data-residency docs don't cover this. Missing for 10: any documentation of telemetry collection or an opt-out/disable mechanism, privacy policy statement on usage tracking, self-host confirmation of no phone-home behavior.

   ⚑ flag

Call control

1. developerEscalate a live call to a human with warm or blind transfer, passing context along

   weight 2 · round to Retell AI
   Retell AI~partialclaimed4/10

   Retell's function-calling docs list 'transfer calls' as a built-in agent action alongside ending calls, booking appointments, etc., which supports the general concept of escalating a call to a human. However, the evidence never distinguishes warm vs. blind transfer modes nor describes passing conversational context/metadata to the receiving human agent. missing for 10: explicit warm-transfer vs blind-transfer configuration, evidence of context/data hand-off to the human agent, and any hands-on confirmation of this feature working in practice.

   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence in the pack describes call transfer functionality (warm or blind) to a human agent, or context handoff during a live call; the closest items relate to model switching, summaries, and telephony/SIP trunking but not transfer escalation.

   ⚑ flag

2. developerMy agent can send DTMF keypresses, navigate IVR menus, and detect or leave voicemail

   weight 1 · round drawn
   Retell AI—none0/10

   The evidence pack covers function calling, custom telephony/SIP trunking, transcription, and MCP tool integration, but nowhere mentions DTMF keypress sending, IVR menu navigation, or voicemail detection/leaving capabilities. This is a fair capability question for a telephony voice-agent platform, but no evidence confirms it is supported.

   ⚑ flag

   Bolna—none0/10

   No evidence in the pack mentions DTMF keypress sending, IVR menu navigation, or voicemail detection/leaving; only unrelated telephony features like SIP trunking, call summaries, and workflows are documented.

   ⚑ flag

Campaigns

1. founderRun batch outbound call campaigns with scheduling and throughput controls

   weight 2 · round to Bolna
   Retell AI—none0/10

   Docs describe outbound vs inbound concurrency reservation (retell-docs-11, retell-docs-41) and custom telephony/SIP integration, but there is no evidence of a batch outbound campaign feature — no mention of scheduling calls, uploading contact lists, or campaign-level throughput controls beyond general concurrency limits. Axis is plausible for a voice-agent platform but unsupported by the evidence pack.

   • [claimed-docs] “Reserved inbound concurrency protects inbound calls from being crowded out by outbound traffic.”
   • [claimed-docs] “When `reserved_inbound_concurrency` is configured, outbound calls can use at most your concurrency limit minus the reserved amount.”
   • [claimed-docs] “Integrate Retell voice agents with your own telephony provider using elastic SIP trunking or imported numbers from Twilio, Telnyx, and Vonag…”

   proof ↗⚑ flag

   Bolna~partialprobed5/10

   The CLI explicitly manages 'batches' of calls alongside agents/phone numbers, and marketing copy claims support for 'thousands of inbound and outbound calls every minute,' plus a workflows API for multi-step outreach with waits/retries — together implying batch campaign and throughput capability. However, there's no explicit documentation of scheduling controls (e.g., time windows, campaign start/stop) or throughput/rate-limiting configuration for outbound campaigns specifically. Missing for 10: explicit scheduling/calendar controls for campaigns, documented throughput/rate-limit configuration knobs, and any hands-on/independent evidence of batch campaign execution.

   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”
   • [claimed-docs] “Build multi-step outreach sequences that combine voice agent calls, WhatsApp messages, API calls, waits and retries, driven entirely through…”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

Numbers

1. developerProvision phone numbers and run both inbound and outbound calls through the platform's API

   weight 3 · round to Retell AI
   Retell AI✓fullprobed8/10

   Retell's docs show phone-number provisioning via native assignment (docs-32) or importing/SIP-trunking your own numbers from Twilio/Telnyx/Vonage (docs-10,40,49), and both inbound and outbound calling are explicitly supported and distinguished (reserved inbound concurrency vs. outbound traffic in docs-11/41). Full API/SDK coverage for voice endpoints (docs-2,33,46) and a CLI to manage phone numbers (docs-3,21) round out programmatic control, with a working keyless CLI/MCP probe corroborating API-level access (retell-probe-rt-1/2). Missing for 10: explicit documentation of a native 'buy a new number' provisioning endpoint (as opposed to importing existing numbers) and a concrete outbound-call code example.

   • [claimed-docs] “Build your first Retell AI phone agent in 15 minutes: create an account, pick a template, test in the dashboard, deploy to a phone number, a…”
   • [claimed-docs] “Integrate Retell voice agents with your own telephony provider using elastic SIP trunking or imported numbers from Twilio, Telnyx, and Vonag…”
   • [claimed-docs] “Reserved inbound concurrency protects inbound calls from being crowded out by outbound traffic.”
   • [claimed-docs] “This guide shows how to integrate Retell agents with your telephony provider and use your own numbers.”
   • [claimed-docs] “When `reserved_inbound_concurrency` is configured, outbound calls can use at most your concurrency limit minus the reserved amount.”
   • [claimed-docs] “You set up a SIP trunk, configure your number to point to it, and import that number to Retell.”
   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [claimed-docs] “Install the Retell CLI to manage agents, phone numbers, knowledge bases, and other Retell resources from your terminal with simple commands.”
   • [claimed-docs] “The Retell CLI lets you manage Retell resources from your terminal.”
   • [probe] “PROBE runtime (recorded 2026-09-05): `npx -y @retell-ai/retell-cli --version` printed `retell 0.13.0 (OpenAPI 3.0.0, catalog v4)` keylessly …”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna~partialprobed6/10

   Bolna's API/CLI clearly support placing outbound calls and receiving inbound calls (quickstart shows placing a call and fetching transcript via API, CLI manages calls and phone numbers, marketing claims thousands of inbound/outbound calls per minute), and BYOT lets you attach SIP trunks/numbers. However there's no explicit documented endpoint for provisioning/purchasing new phone numbers through the API itself — only CLI mention of managing 'phone numbers' and bringing your own trunk. Missing for 10: explicit phone-number provisioning API endpoint/documentation, independent confirmation of end-to-end inbound+outbound flow.

   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “The Bolna CLI (bolna) is a single Go binary that lets you manage agents, calls, phone numbers, and batches directly from your terminal”
   • [claimed-docs] “Bring Your Own Telephony (BYOT) lets you connect any standards-compliant SIP trunk to the Bolna platform.”
   • [claimed-docs] “Power thousands of inbound and outbound calls every minute with human-like, multilingual intelligence”
   • [probe] “official CLI documented at https://www.bolna.ai/docs/cli/introduction”

   proof ↗⚑ flag

Sip

1. platform-engineerConnect my own carrier or PBX via SIP trunking (or import Twilio/Telnyx numbers) instead of being locked to bundled telephony

   weight 2 · round drawn
   Retell AI✓fullclaimed8/10

   Official docs explicitly describe elastic SIP trunking and importing numbers from Twilio, Telnyx, and Vonage, walking through setting up a SIP trunk and pointing/importing numbers into Retell — directly matching the story. This is first-party documentation without independent hands-on corroboration of the SIP flow itself. Missing for 10: independent/community verification of a real SIP trunk setup working end-to-end, and detail on carrier-specific edge cases (codecs, failover, latency).

   • [claimed-docs] “Integrate Retell voice agents with your own telephony provider using elastic SIP trunking or imported numbers from Twilio, Telnyx, and Vonag…”
   • [claimed-docs] “This guide shows how to integrate Retell agents with your telephony provider and use your own numbers.”
   • [claimed-docs] “You set up a SIP trunk, configure your number to point to it, and import that number to Retell.”

   proof ↗⚑ flag

   Bolna✓fullclaimed8/10

   Bolna explicitly documents 'Bring Your Own Telephony (BYOT)' allowing any standards-compliant SIP trunk to connect to the platform, plus IP whitelisting requirements for the connection, directly addressing carrier/PBX independence from bundled telephony. missing for 10: explicit step-by-step Twilio/Telnyx number import walkthrough and independent/hands-on verification of SIP trunk setup working end-to-end.

   • [claimed-docs] “Bring Your Own Telephony (BYOT) lets you connect any standards-compliant SIP trunk to the Bolna platform.”
   • [claimed-docs] “Whitelist all three IPs on your server or firewall”

   proof ↗⚑ flag

Analytics

1. ai-native userThe platform's AI reviews my calls for me — scoring quality, flagging failures, and analyzing resolution automatically

   weight 2 · round to Retell AI
   Retell AI~partialclaimed6/10

   Retell's AI QA feature automatically scores sampled calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage, and the Analytics dashboard tracks success rate and other metrics, directly matching the story's core ask of automated call scoring and quality flagging. However, evidence shows AI QA only evaluates a 'sampled set' of calls (not all calls) against user-configured rules, and there's no documented automatic 'resolution analysis' narrative beyond metrics/dashboards, nor independent hands-on validation of AI QA accuracy. missing for 10: evidence of full (non-sampled) coverage, independent/third-party validation of AI QA scoring accuracy, and detail on automated resolution/failure-cause analysis beyond configured metrics.

   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “Built-in call success and sentiment scoring, plus custom fields synced to your CRM.”

   proof ↗⚑ flag

   Bolna~partialclaimed3/10

   Bolna offers post-call analysis primitives — configurable extraction-categories (bolna-docs-1) and toggleable call summaries (bolna-docs-2) — which could be used to build custom scoring/flagging, but there's no documented automated QA/quality-scoring, failure-flagging, or resolution-analysis feature out of the box. Missing for 10: dedicated call-scoring/QA dashboard, automatic failure detection, resolution-analysis reporting, and independent evidence these extraction fields are used for review purposes.

   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”

   proof ↗⚑ flag

2. founderSee call analytics — success rates, durations, outcomes, sentiment — in dashboards without building my own

   weight 2 · round to Retell AI
   Retell AI✓fullclaimed8/10

   Retell docs describe a built-in Analytics dashboard with charts, filters, and breakdowns for success rate, latency, cost, and concurrency, plus AI QA scoring for sentiment, hallucination, and tool usage—directly matching the founder's need for out-of-box call analytics. Missing for 10: independent/hands-on confirmation of dashboard usability and no evidence of exportable reports or deeper outcome breakdowns beyond what's documented.

   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”
   • [claimed-docs] “Built-in call success and sentiment scoring, plus custom fields synced to your CRM.”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence only shows API-level features like call summaries (call_summary_enabled) and extraction categories, but there is no mention of a dashboard UI presenting success rates, durrations, outcomes, or sentiment analytics — missing for 10: any dashboard/UI screenshot or docs describing aggregated call analytics views.

   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”

   proof ↗⚑ flag

Monitoring

1. platform-engineerMonitor live calls in production and get alerts when agents misbehave or error rates spike

   weight 1 · round to Retell AI
   Retell AI~partialclaimed6/10

   Retell provides real building blocks for production monitoring — a customizable analytics dashboard tracking success rate, latency, cost and concurrency (retell-docs-13/42), AI QA that scores calls for hallucination, sentiment and tool-usage issues (retell-docs-14/43), and webhooks that push real-time event notifications (retell-docs-12/24) which a platform engineer could wire into an alerting pipeline. However there is no documented native alerting/threshold system (e.g., automatic notification when error rates spike or an agent misbehaves) or a live in-call monitoring view — engineers must build that themselves on top of webhooks/dashboard APIs. Missing for 10: built-in threshold-based alerts or anomaly detection, a real-time 'in-progress calls' monitoring view, and any independent evidence that alerting/monitoring works reliably in production.

   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence covers call summaries, extraction categories, transcripts, CLI, MCP, and SIP/telephony features, but nothing describes live-call monitoring dashboards, real-time observability, or alerting on agent misbehavior or error-rate spikes. No mention of metrics, alert thresholds, webhooks for anomaly detection, or a monitoring console for platform engineers. Missing for 10: real-time monitoring dashboard, alerting/notification system for errors or misbehavior, error-rate tracking, on-call/integration with observability tools.

   ⚑ flag

Testing

1. developerTest agents with simulated conversations or evals before putting them on real phone calls

   weight 2 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell's dashboard has a free 'Test' web-call button that lets developers try an agent before assigning it to a real phone number, and AI QA can score calls on hallucination, accuracy, sentiment, etc., which supports some testing/analytics workflow. However there's no documented feature for automated simulated-conversation test suites or eval scripts run pre-deployment — AI QA appears to operate on sampled real calls rather than synthetic scripted evals. Missing for 10: dedicated simulation/eval framework for scripted test conversations, batch eval tooling, and any independent verification that pre-call testing catches issues before production use.

   • [claimed-docs] “Click the "Test" button to start a web call with your agent... This step is free and doesn't need a phone number or payment method.”
   • [claimed-docs] “Click the "Test" button to start a web call with your agent”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”

   proof ↗⚑ flag

   Bolna—none0/10

   No evidence of any simulated conversation testing, evals, or pre-production testing framework for agents; the evidence pack only covers deployment, telephony, providers, pricing, and SDKs. Missing for 10: any mention of test/eval tooling, simulated call testing, or conversation quality scoring before live calls.

   ⚑ flag

Post call

1. developerExtract structured data from every call — outcomes, entities, dispositions — delivered via API or webhook after the call

   weight 2 · round to Retell AI
   Retell AI✓fullclaimed7/10

   Retell explicitly supports post-call structured extraction: built-in call success/sentiment scoring plus custom fields synced to CRM, delivered via real-time webhooks and viewable/aggregated in the analytics/AI QA dashboards. This directly covers outcomes (success rate), dispositions (sentiment), and entities (custom fields) delivered via API/webhook as the story requires. Missing for 10: no independent/hands-on confirmation of the specific post-call-analysis JSON schema or webhook payload structure, and no detail on how custom entity fields are defined/configured.

   • [claimed-docs] “Built-in call success and sentiment scoring, plus custom fields synced to your CRM.”
   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”
   • [claimed-docs] “Build custom Retell analytics dashboards to track call and chat metrics like success rate, latency, cost, and concurrency, with charts, filt…”
   • [claimed-docs] “The Analytics dashboard charts your call and chat data so you can see how your agents are performing over time.”
   • [claimed-docs] “AI QA scores Retell calls on hallucination, knowledge base accuracy, latency, sentiment, and tool usage to surface quality trends and issues…”
   • [claimed-docs] “AI QA automatically evaluates a sampled set of your calls against rules and metrics you configure.”

   proof ↗⚑ flag

   Bolna~partialclaimed6/10

   Bolna provides extraction-categories API to attach custom entity/data extraction to agents and a call_summary_enabled toggle for summaries, plus transcript fetch via API — covering entities, summaries, and outcomes. However, there's no explicit documentation of a unified structured 'disposition' field, no clear webhook delivery mechanism for post-call structured payloads (only API fetch is shown), and no example of the combined extraction+summary+disposition JSON schema. missing for 10: webhook-based delivery of extraction results, documented disposition/outcome field, end-to-end example combining all three data types in one payload.

   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”
   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”

   proof ↗⚑ flag

Tools

1. ai-native userMy voice agent can plug in MCP servers as tool sources so one integration grants it whole toolsets mid-call

   weight 2 · round to Retell AI
   Retell AI✓fullclaimed8/10

   Retell documents connecting single/multi-prompt voice agents to remote MCP servers so the agent can call the server's tools mid-call (retell-docs-6/23/36), directly matching the story, and this is distinct from Retell's own client-side MCP server for building agents. missing for 10: independent third-party corroboration of mid-call MCP tool invocation in production (only first-party docs and a probe of the client-facing MCP server, not the agent-as-MCP-client tool-call path, are available).

   • [claimed-docs] “Connect a Retell single- or multi-prompt agent to a remote MCP server so it can call the server's tools during a live voice or chat conversa…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote Model Context Protocol (MCP) server, and the agent can call that server's tools durin…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote [Model Context Protocol (MCP)] server, and the agent can call that server's tools dur…”
   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence only shows Bolna exposing its OWN MCP server so external clients (Claude, Cursor, Windsurf) can manage a Bolna account (bolna-docs-17, bolna-probe-3) — the reverse direction of the story, which asks whether a Bolna voice agent can consume external MCP servers as tool sources mid-call. No documentation shows Bolna agents acting as an MCP client or importing toolsets from third-party MCP servers during a call. missing for 10: any evidence of Bolna voice agents connecting to external MCP servers as tool sources, mid-call toolset loading via MCP.

   • [claimed-docs] “Connect Claude, Cursor, Windsurf, or any MCP client to your Bolna account with the Bolna MCP server.”
   • [probe] “official MCP server documented at https://www.bolna.ai/docs/build-with-ai/mcp”

   proof ↗⚑ flag

2. developerMy agent can call external APIs and custom functions mid-conversation and speak the result without awkward dead air

   weight 3 · round to Retell AI
   Retell AI~partialprobed6/10

   Retell's docs clearly document function calling that lets agents call external APIs mid-conversation (retell-docs-5, retell-docs-35) and even connect to remote MCP servers to invoke tools live during a call (retell-docs-6, retell-docs-23, retell-docs-36), confirmed by a keyless runtime probe showing the hosted MCP server exposing invoke_api_endpoint tools (retell-probe-rt-2). However, no evidence specifically addresses the 'no awkward dead air' requirement — there's no documented filler-speech, streaming-response, or latency-masking mechanism specifically tied to function-call execution; transcription-mode docs (retell-docs-9/39/48) discuss general STT latency tradeoffs, not function-call dead-air handling. missing for 10: explicit filler/backchannel speech during function execution, hands-on demonstration of seamless mid-call tool latency, independent confirmation of no dead-air behavior.

   • [claimed-docs] “Function calling lets Retell single or multi-prompt agents take real actions — transfer calls, end calls, book appointments, send SMS, and c…”
   • [claimed-docs] “Function calling transforms your AI agent from a conversational interface into an action-oriented assistant.”
   • [claimed-docs] “Connect a Retell single- or multi-prompt agent to a remote MCP server so it can call the server's tools during a live voice or chat conversa…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote Model Context Protocol (MCP) server, and the agent can call that server's tools durin…”
   • [claimed-docs] “Connect your single- or multi-prompt agent to a remote [Model Context Protocol (MCP)] server, and the agent can call that server's tools dur…”
   • [probe] “PROBE runtime (recorded 2026-09-05): the hosted MCP server at https://mcp.retellai.com completed a full KEYLESS JSON-RPC initialize handshak…”

   proof ↗⚑ flag

   Bolna—none0/10

   The evidence pack covers extraction categories, call summaries, workflows, and custom LLM providers, but nothing describes an agent invoking external APIs or custom functions mid-call and voicing the result seamlessly. Missing for 10: documentation of a function-calling/tool-use API, examples of mid-call API invocation, and any mention of latency-masking/filler techniques to avoid dead air.

   ⚑ flag

Recording

1. platform-engineerRetrieve full call recordings and transcripts programmatically for every call

   weight 2 · round to Retell AI
   Retell AI~partialclaimed6/10

   Docs confirm that Retell stores per-call transcripts and recordings (referenced in data-retention docs) and that full voice/chat API endpoint coverage exists via official SDKs, implying programmatic retrieval, but no evidence pack item explicitly documents a 'get call' or 'list calls' API endpoint returning recording URLs/transcript text, nor examples of pulling them via SDK/CLI. Missing for 10: explicit API reference for call/recording/transcript retrieval endpoints, CLI/SDK code samples showing recording download or transcript fetch, and any independent confirmation of this working end-to-end.

   • [claimed-docs] “Configure per-agent data retention to automatically delete call and chat data — transcripts, recordings, and logs — after a set period for c…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent. After the retention period expires, call and chat data associated with tha…”
   • [claimed-docs] “Retell allows you to configure a data retention period per agent.”
   • [claimed-docs] “Official Retell SDKs for Node.js and Python. Typed clients with API key auth, structured errors, and full voice and chat endpoint coverage.”
   • [claimed-docs] “Retell provides official SDKs for Node.js and Python to simplify integration with our platform.”
   • [claimed-docs] “Webhooks allow your application to receive real-time notifications about events that occur in your Retell AI account.”
   • [claimed-docs] “webhooks push data to your application as events happen, making your integrations more efficient and responsive.”

   proof ↗⚑ flag

   Bolna~partialclaimed5/10

   Docs confirm fetching call transcripts via API (quickstart mentions 'fetch the transcript') and call summaries can be toggled, but there is no explicit documentation of a dedicated recordings-retrieval endpoint or bulk/programmatic export for all calls. missing for 10: explicit call-recording download/API endpoint, confirmation that recordings are retained and accessible for every call, and independent verification of transcript completeness/format.

   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”
   • [claimed-docs] “Call summaries are an agent-level toggle: call_summary_enabled (boolean, off by default) on the agent create and update APIs”
   • [claimed-docs] “POST /agent/{agent_id}/extraction-categories — create a category (name + model) and attach it to an agent”

   proof ↗⚑ flag

Transcription

1. developerGet accurate real-time transcription with control over the STT provider, language models, or key terms

   weight 2 · round to Bolna
   Retell AI~partialcommunity4/10

   Retell docs confirm real-time transcription with a documented latency/accuracy trade-off (interim vs context-aware endpointing), giving developers some control over accuracy tuning, and community notes hint at underlying provider choices (e.g., Deepgram) for voice pipelines. However, there is no documented ability to select or swap STT providers, choose an ASR language model, or configure custom vocabulary/key-term boosting for transcription accuracy. Missing for 10: explicit STT provider selection API, language model choice for transcription, custom vocabulary/key-term boosting support, and independent accuracy benchmarks.

   • [claimed-docs] “Pick the right Retell transcription mode to balance accuracy against latency — interim results for speed or context-aware results for higher…”
   • [claimed-docs] “Real time transcription is often a trade off between latency and accuracy.”
   • [claimed-docs] “optimize for speed: uses the latest interim results with a low endpointing setting... optimize for accuracy: uses the results with a higher …”
   • [community] “Founder (yanyan_evie) noted voice provider costs differ: 'The different providers have different prices. openai tts & deepgram are cheaper, …”

   proof ↗⚑ flag

   Bolna~partialclaimed5/10

   Docs confirm STT provider choice (Deepgram, Azure, ElevenLabs) and full LLM control including custom OpenAI-compatible endpoints, plus transcript retrieval via API, giving developers real provider/model flexibility. However there is no evidence of key-term/vocabulary boosting or accuracy tuning controls, nor any real-time transcription accuracy benchmarks. Missing for 10: key-term/keyword-boost configuration, accuracy/latency benchmarks for real-time transcription, and independent validation of transcription quality.

   • [claimed-docs] “Bolna supports Deepgram, Azure, ElevenLabs, and more.”
   • [claimed-docs] “For custom llm simply keep provider in the llm_agent key as custom and add a openai compatible base_url”
   • [claimed-docs] “Make your first Voice AI call with the Bolna API — verify your key, get an agent, place a call, and fetch the transcript in about five minut…”

   proof ↗⚑ flag

Voices

1. founderClone a custom brand voice and use it for my agents, with a documented consent process

   weight 2 · round to Retell AI
   Retell AI~partialclaimed5/10

   Retell documents voice cloning from uploaded audio files (up to 25 files) and lets you attach the cloned voice to an agent via the voice selector, covering the core 'clone and use a custom voice' capability. However, none of the evidence describes any documented consent-verification step (e.g., consent recording, rights attestation) as part of the cloning flow. Missing for 10: an explicit consent-collection/verification mechanism in the clone-voice API or dashboard docs, and any compliance guidance tying voice cloning to consent requirements.

   • [claimed-docs] “Add custom voices to your Retell agent — search ElevenLabs community voices, import a voice clone, or train a clone for a unique brand-speci…”
   • [claimed-docs] “Clone a voice from audio files”
   • [claimed-docs] “Audio files to use for voice cloning. Up to 25 files allowed.”
   • [claimed-docs] “You can also add a voice clone by clicking "Add custom voice" in the voice selector.”

   proof ↗⚑ flag

   Bolna—none0/10

   Evidence shows Bolna lets founders choose among third-party voices/accents/styles (bolna-docs-8) and integrates providers like ElevenLabs (bolna-docs-6), but there is no mention of a voice-cloning feature for a custom brand voice, nor any documented consent process for cloning. Missing for 10: voice cloning capability, consent/verification workflow documentation, any policy on brand voice usage.

   • [claimed-docs] “You can choose different voices, accents, and speaking styles to match your brand.”
   • [claimed-docs] “Bolna supports Deepgram, Azure, ElevenLabs, and more.”

   proof ↗⚑ flag

2. developerChoose from a broad voice library or plug in multiple TTS providers to get the voice I want

   weight 2 · round to Retell AI
   Retell AI✓fullcommunity7/10

   Docs confirm a searchable voice library (ElevenLabs community voices) plus voice cloning options (retell-docs-7, retell-docs-37, retell-docs-38), and a founder community comment independently confirms multiple underlying TTS providers (OpenAI TTS, Deepgram, ElevenLabs) with different pricing tiers (retell-comm-10), showing developers can indeed pick across providers/voices. Missing for 10: a first-party docs page enumerating all supported TTS providers and API-level provider-switching parameters beyond the voice-selector UI, and independent hands-on comparison of voice quality across providers.

   • [claimed-docs] “Add custom voices to your Retell agent — search ElevenLabs community voices, import a voice clone, or train a clone for a unique brand-speci…”
   • [claimed-docs] “You can also add a voice clone by clicking "Add custom voice" in the voice selector.”
   • [claimed-docs] “In the voice selector, you can click "Add custom voice" to search and add publicly available community voices.”
   • [community] “Founder (yanyan_evie) noted voice provider costs differ: 'The different providers have different prices. openai tts & deepgram are cheaper, …”

   proof ↗⚑ flag

   Bolna~partialclaimed6/10

   Docs confirm multiple TTS providers (Deepgram, Azure, ElevenLabs, and more) plus voice/accent/style customization, satisfying the 'plug in providers' part of the story. However, there's no evidence of a broad pre-built voice library or catalog to browse/select from, only provider integration. Missing for 10: evidence of a large built-in voice library/catalog, provider-count breadth beyond three named examples, independent/hands-on confirmation of voice quality or selection UX.

   • [claimed-docs] “Bolna supports Deepgram, Azure, ElevenLabs, and more.”
   • [claimed-docs] “You can choose different voices, accents, and speaking styles to match your brand.”

   proof ↗⚑ flag