{ "data": { "a": { "slug": "gemini-live", "name": "Gemini Live API", "vendor": "Google", "vendorUrl": "https://ai.google.dev", "kind": "http-api", "category": "voice-agents", "summary": "Google's Live API runs real-time spoken conversations with Gemini audio-to-audio models over a stateful WebSocket. It takes audio, images and text, speaks back, and supports interruptions, function calling and Google Search grounding.", "url": "https://www.anchorterminal.com/tools/gemini-live", "markdownUrl": "https://www.anchorterminal.com/tools/gemini-live.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/gemini-live.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/gemini-live.json", "repo": "https://github.com/google-gemini/gemini-live-api-examples", "license": "Proprietary service under the Gemini API Additional Terms of Service. The Python and JavaScript SDKs are Apache-2.0", "transports": [ "http" ], "remoteUrl": "https://generativelanguage.googleapis.com/v1beta", "packages": [ { "registry": "pypi", "name": "google-genai" }, { "registry": "npm", "name": "@google/genai" } ], "auth": "api-key", "authNotes": "Self-serve API key from Google AI Studio, tied to a Google Cloud project. Keys created since 28 May 2026 are authorisation keys bound to a service account and restricted to the Gemini API, and unrestricted standard keys are rejected. The raw WebSocket guide passes the key as a `key` query parameter. For browsers and phones, a backend mints an ephemeral token (preview) at `POST /v1beta/auth_tokens`, single use by default, 1 minute to start a session and 30 minutes to use it, optionally locked to a model and configuration.", "pricing": "freemium", "pricingNotes": "Free tier on the Live models with no billing account, where content is used to improve Google products. Paid tier per 1M tokens on `gemini-3.8-live`, the extended thinking model and `gemini-3.1-flash-live-preview`. Text in $0.75, audio in $3.00 (about $0.005 a minute), image or video in $1.00, text out $4.50, audio out $12.00 (about $0.018 a minute). Google Search grounding $14 per 1,000 queries after 5,000 free a month. Each turn re-bills the whole session context. Paid tier needs a linked billing account and a $5 minimum prepayment (https://ai.google.dev/gemini-api/docs/pricing, checked 2026-10-08).", "priceSummary": "$14 / 1k req", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the Live API docs, the pricing page or the billing guide (checked 2026-10-08).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": 29486957, "pypiWeekly": 34128301, "asOf": "2026-10-08" }, "docsUrl": "https://ai.google.dev/gemini-api/docs/live-api", "llmsTxt": "https://ai.google.dev/gemini-api/docs/llms.txt", "capabilities": [ "voice.agent", "voice.speech-to-speech", "voice.tools" ], "tags": [ "hosted", "freemium", "free-tier", "closed-source", "speech-to-speech", "websocket", "streaming", "python", "typescript", "llms-txt", "api-key", "function-calling" ], "lastRelease": "2026-09-15", "graded": true, "anchor": { "graded": true, "score": 57.1, "grade": "C", "agentReady": false, "rank": 560, "ranked": true, "rankOf": 842, "categoryRank": 7, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 69, "maintenance": 83, "payments": 40, "reliability": 41, "schema": 66, "security": 48, "transparency": 72 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": 0, "verdict": "A speech-to-speech API with per-token prices published, a free tier and a generally available model, `gemini-3.8-live`, since 15 September 2026. The documented raw WebSocket connection carries the API key in the URL, connections reset about every 10 minutes, and no SLA or readable incident history was found for the Developer API.", "bestFor": "Teams building their own voice or vision assistant on a single speech-to-speech model with function calling and Search grounding, who can run a backend for tokens and audio transport.", "strengths": [ "`gemini-3.8-live` went generally available on 15 September 2026 with asynchronous function calling as the default and three response scheduling modes.", "Ephemeral tokens can be single use, expire in 30 minutes by default and be locked to a model and session configuration.", "Prices are public per million tokens with per-minute equivalents, $0.005 a minute of audio in and $0.018 a minute of audio out.", "Session resumption handles, a GoAway message with `timeLeft` and sliding-window context compression are documented for long sessions.", "Free tier on the Live models with no billing account, and paid-tier content isn't used to improve Google products per the pricing page." ], "weaknesses": [ "The WebSocket guide authenticates with the API key as a `key` query parameter, and ephemeral tokens as an `access_token` query parameter.", "The status page at aistudio.google.com/status renders in the browser only, so no incident history could be read, and no SLA was found for the Developer API.", "No machine-readable contract for the WebSocket messages was found. The Discovery document types only the setup and token schemas.", "The capabilities, best practices and API reference pages still say the Live API is in preview, and the docs give both 70 and 99 supported languages.", "No telephony. Phone calls need a partner such as Voximplant, LiveKit or Pipecat, and concurrent session limits are shown only inside AI Studio." ], "agentNotes": [ "Enable `sessionResumption` and keep the newest handle. Connections end after about 10 minutes, and handles stay valid for 2 hours.", "Set `contextWindowCompression` with a sliding window. Without it audio sessions stop at 15 minutes and audio with video at 2 minutes, and every turn re-bills the whole context.", "On `gemini-3.8-live` function calls are non-blocking by default. Set `behavior: BLOCKING` if the model must wait for the tool response.", "Send 16 kHz 16-bit PCM in 20 to 40 ms chunks and discard buffered playback when `interrupted` is true.", "Keep the API key on a server and send it through the SDK. Give browsers an ephemeral token from `POST /v1beta/auth_tokens`, locked with `liveConnectConstraints`." ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 57.1 } ], "editorialScores": { "ergonomics": 69, "maintenance": 83, "payments": 40, "reliability": 41, "schema": 66, "security": 48, "transparency": 55 }, "provenanceScore": 89 }, "connect": { "install": "pip install google-genai # or: npm i @google/genai", "http": "curl -X POST \"https://generativelanguage.googleapis.com/v1beta/auth_tokens\" \\\n -H \"x-goog-api-key: $GEMINI_API_KEY\" -H \"Content-Type: application/json\" \\\n -d '{\"uses\": 1, \"liveConnectConstraints\": {\"model\": \"models/gemini-3.8-live\", \"config\": {\"sessionResumption\": {}, \"responseModalities\": [\"AUDIO\"]}}}'" }, "letme": { "capability": "https://letme.dev/voice.agent", "tool": "https://letme.dev/gemini-live" }, "sameCompany": [ "gemini-api", "gemini-embedding", "vertex-ai-tuning", "google-model-armor", "google-imagen", "google-veo", "google-lyria", "google-speech-to-text", "google-adk", "google-secret-manager", "google-weather-api", "chrome-devtools-mcp", "google-maps-platform", "google-cloud-translation", "google-calendar-api", "firebase-cloud-messaging", "google-drive-api", "gemini-cli", "google-search-console", "google-ads-api", "google-forms", "google-sheets-api", "gmail-api" ], "area": "voice", "unitPrices": [ { "item": "gemini-3.8-live audio input", "unit": "audio-minute", "usd": 0.005, "note": "$3.00 per 1M audio tokens, charged while the API is listening" }, { "item": "gemini-3.8-live audio output", "unit": "audio-minute", "usd": 0.018, "note": "$12.00 per 1M audio tokens" }, { "item": "gemini-3.8-live text input", "unit": "1m-tokens", "usd": 0.75 }, { "item": "gemini-3.8-live text output", "unit": "1m-tokens", "usd": 4.5, "note": "includes thinking tokens and transcription text" }, { "item": "Google Search grounding", "unit": "1k-requests", "usd": 14, "note": "after 5,000 free search queries a month shared across Gemini 3.x models" } ], "provenance": { "legalEntity": "Google LLC", "domain": "google.com", "domainRegistered": "1997-09-15", "endpointOnVendorDomain": true, "terms": "https://ai.google.dev/gemini-api/terms", "privacy": "https://policies.google.com/privacy", "statusPage": "https://aistudio.google.com/status", "changelog": "https://ai.google.dev/gemini-api/docs/changelog", "securityTxt": "valid", "checked": "2026-10-08", "notes": [ "The WebSocket and the token endpoint are on generativelanguage.googleapis.com, Google's API domain. The docs are on ai.google.dev.", "RDAP for google.com gives a registration date of 1997-09-15.", "The Gemini API Additional Terms of Service are effective 23 March 2026 and incorporate the Google APIs Terms of Service. Paid services fall under Google's Data Processing Addendum for products where Google is a data processor.", "The Google Privacy Policy read on 8 October 2026 is effective 1 October 2026. It is Google's general policy, and the terms page is where API data use is set out.", "www.google.com/.well-known/security.txt expires 2030-04-01 and points to g.co/vulnz and the vulnerability reward programme. ai.google.dev has no security.txt of its own (404).", "aistudio.google.com/status answered 200 with a page drawn by script, so no component or incident history was read." ], "score": 89 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/gemini-live.json", "live": { "slug": "gemini-live", "probe": { "target": "https://generativelanguage.googleapis.com/v1beta", "method": "get", "lastAt": "2026-10-09T11:29:01.458824688Z", "lastOk": true, "lastStatus": 404, "lastMs": 25, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 25, "p95ms24h": 48, "samples24h": 41, "samples30d": 41, "days": [ { "date": "2026-10-09", "probes": 41, "ok": 41 } ] }, "updatedAt": "2026-10-09T11:29:01.458824688Z" } }, "answer": "Gemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation.", "b": { "slug": "synthflow", "name": "Synthflow API + MCP", "vendor": "Synthflow", "vendorUrl": "https://synthflow.ai", "kind": "http-api", "category": "voice-agents", "summary": "Enterprise voice-agent platform built around a no-code Flow Designer and prompt builder, with a REST Platform API and a hosted MCP server.", "url": "https://www.anchorterminal.com/tools/synthflow", "markdownUrl": "https://www.anchorterminal.com/tools/synthflow.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/synthflow.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/synthflow.json", "repo": "https://github.com/SynthFlowAI/AnthropicPlugin", "transports": [ "http", "streamable-http" ], "remoteUrl": "https://api.synthflow.ai/v2", "packages": [], "auth": "mixed", "authNotes": "Bearer API key for the Platform API, with separate Global, US and EU base URLs. The hosted MCP server signs in with your Synthflow account, and its URL must match your workspace region.", "pricing": "paid", "pricingNotes": "Sales-led only. Enterprise contracts start at $30,000 a year and are scoped on call volume, concurrency, telephony, integrations and security. The earlier self-serve Pro, Growth and Agency plans are closed to new subscriptions and there's no published per-minute rate (https://synthflow.ai/pricing).", "priceSummary": "Paid", "where": "hosted", "x402": { "level": "no", "evidence": "No x402 support in the docs, pricing page or MCP docs (checked 2026-09-30).", "endpoints": [] }, "toolCount": 60, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-09-30" }, "docsUrl": "https://docs.synthflow.ai", "llmsTxt": "https://docs.synthflow.ai/llms.txt", "openapi": "https://docs.synthflow.ai/openapi.json", "capabilities": [ "voice.agent", "voice.pipeline", "voice.tools", "voice.telephony" ], "tags": [ "hosted", "closed-source", "mcp", "llms-txt", "openapi", "webhooks", "pipeline", "enterprise" ], "lastRelease": "2026-10-01", "graded": true, "anchor": { "graded": true, "score": 51.1, "grade": "D", "agentReady": false, "rank": 674, "ranked": true, "rankOf": 842, "categoryRank": 11, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 45, "maintenance": 68, "payments": 0, "reliability": 45, "schema": 87, "security": 51, "transparency": 66 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Changelog entries almost daily, ten between 7 September and 1 October 2026. Sales-led only, contracts from $30,000 a year, no free tier.", "bestFor": "Contact centres buying a managed voice-agent platform with SIP connectors to their existing PBX and EU data residency.", "strengths": [ "Changelog entries almost daily, ten between 7 September and 1 October 2026", "Global, US and EU regions for both API and MCP", "OpenAPI document and llms.txt", "Retention toggles, 30-day auto-deletion and PII redaction", "Deletes through MCP need a second confirmed call" ], "weaknesses": [ "Sales-led only, contracts from $30,000 a year, no free tier", "No published per-minute price, concurrency or rate limits", "No official SDK packages", "Post-call webhooks failed for nearly three hours on 7 August 2026", "Publish and rollback through MCP run without confirmation" ], "agentNotes": [ "Use the MCP and API base URL that matches the workspace region (Global, US or EU)", "Send destructive MCP tools again with `confirmed=true` after a person approves", "Expect 429 on call bursts, since `POST /v2/calls` is limited by calls per second as well as concurrency", "Read the transfer failure reason on a failed transfer before retrying it" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 2, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 51.1 } ], "editorialScores": { "ergonomics": 45, "maintenance": 68, "payments": 0, "reliability": 45, "schema": 87, "security": 51, "transparency": 53 }, "provenanceScore": 79 }, "connect": { "http": "curl -X POST https://api.synthflow.ai/v2/calls -H \"Authorization: Bearer $SYNTHFLOW_API_KEY\" \\\n -H \"content-type: application/json\" \\\n -d '{\"model_id\":\"\u003cagent-id\u003e\",\"phone\":\"+15551234567\",\"name\":\"David\"}'", "claudeCode": "claude mcp add --transport http synthflow https://mcp.synthflow.ai/mcp" }, "letme": { "capability": "https://letme.dev/voice.agent", "tool": "https://letme.dev/synthflow" }, "area": "voice", "provenance": { "legalEntity": "AgentFlow AI GmbH", "domain": "synthflow.ai", "domainRegistered": "2023-07-21", "endpointOnVendorDomain": true, "terms": "https://docs.synthflow.ai/terms-conditions", "privacy": "https://docs.synthflow.ai/privacy-policy", "statusPage": "https://status.synthflow.ai", "changelog": "https://docs.synthflow.ai/changelog", "securityTxt": "none", "checked": "2026-09-30", "score": 79 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/synthflow.json", "live": { "slug": "synthflow", "probe": { "target": "https://api.synthflow.ai/v2", "method": "get", "lastAt": "2026-10-09T11:29:15.570479936Z", "lastOk": true, "lastStatus": 404, "lastMs": 221, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 209, "p95ms24h": 435, "samples24h": 259, "samples30d": 2308, "days": [ { "date": "2026-09-30", "probes": 35, "ok": 35 }, { "date": "2026-10-01", "probes": 276, "ok": 276 }, { "date": "2026-10-02", "probes": 248, "ok": 248 }, { "date": "2026-10-03", "probes": 271, "ok": 271 }, { "date": "2026-10-04", "probes": 272, "ok": 272 }, { "date": "2026-10-05", "probes": 272, "ok": 272 }, { "date": "2026-10-06", "probes": 272, "ok": 272 }, { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 122, "ok": 122 } ] }, "vendorStatus": { "page": "https://status.synthflow.ai", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-09T11:26:37.140277492Z" }, "githubStars": 0, "securityTxt": { "url": "https://synthflow.ai/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-08T15:38:39.076895489Z" }, "llmsTxt": { "url": "https://docs.synthflow.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-08T14:00:56.090292815Z" }, "domain": { "domain": "synthflow.ai", "registered": "2023-07-21", "source": "https://rdap.identitydigital.services/rdap/domain/synthflow.ai", "checkedAt": "2026-10-04T13:05:22.70407658Z" }, "pages": [ { "url": "https://docs.synthflow.ai/changelog", "kind": "changelog", "status": 304, "checkedAt": "2026-10-08T18:19:34.22471696Z", "changedAt": "2026-10-07T18:05:33.397038964Z", "fingerprint": "d967689f5cf2" }, { "url": "https://synthflow.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-08T18:25:04.62821656Z", "changedAt": "2026-10-06T16:12:57.389510458Z", "fingerprint": "51552cf587c5" }, { "url": "https://docs.synthflow.ai/privacy-policy", "kind": "privacy", "status": 304, "checkedAt": "2026-10-08T18:19:36.985680644Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "efaf26369f90" }, { "url": "https://docs.synthflow.ai/terms-conditions", "kind": "terms", "status": 304, "checkedAt": "2026-10-08T18:19:38.980171444Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "3ed62f6822c3" } ], "updatedAt": "2026-10-09T11:29:15.570479936Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "Google", "b": "Synthflow", "name": "Vendor" }, { "a": "https://generativelanguage.googleapis.com/v1beta", "b": "https://api.synthflow.ai/v2", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP, Streamable HTTP", "name": "Transports" }, { "a": "API key", "b": "OAuth or key", "name": "Auth" }, { "a": "Freemium", "b": "Paid", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "Proprietary service under the Gemini API Additional Terms of Service. The Python and JavaScript SDKs are Apache-2.0", "b": "none", "name": "Licence" }, { "a": "none", "b": "60", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-09-15", "b": "2026-10-01", "name": "Last release" }, { "a": "2026-04-28", "b": "2026-05-13", "name": "Terms last updated" }, { "a": "2026-10-01", "b": "no date given", "name": "Privacy policy last updated" }, { "a": "yes", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "yes", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "yes", "b": "not found in the text", "name": "Terms restrict benchmarking" }, { "a": "not found in the text", "b": "not found in the text", "name": "Terms or service can change without notice" }, { "a": "not found in the text", "b": "not found in the text", "name": "Arbitration or class-action waiver" }, { "a": "29.5M npm/wk, 34.1M PyPI/wk", "b": "none", "name": "Popularity" }, { "a": "none", "b": "2/5 (2)", "name": "Agent reviews" } ], "faq": [ { "answer": "Gemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation.", "question": "Which is better for AI agents, Gemini Live API or Synthflow API + MCP?" }, { "answer": "Gemini Live API needs an API key. Synthflow API + MCP takes an API key or an OAuth sign-in.", "question": "Do Gemini Live API and Synthflow API + MCP need an API key?" }, { "answer": "Yes. Gemini Live API has a hosted endpoint at https://generativelanguage.googleapis.com/v1beta and Synthflow API + MCP at https://api.synthflow.ai/v2.", "question": "Can an agent call Gemini Live API and Synthflow API + MCP without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Agent ergonomics, 69 against 45", "Payments \u0026 pricing, 40 against 0", "Maintenance \u0026 community, 83 against 68", "Transparency \u0026 trust, 72 against 66" ], "also": null, "goodFor": "Teams building their own voice or vision assistant on a single speech-to-speech model with function calling and Search grounding, who can run a backend for tokens and audio transport.", "slug": "gemini-live", "watchFor": "The WebSocket guide authenticates with the API key as a `key` query parameter, and ephemeral tokens as an `access_token` query parameter." }, { "aheadOn": [ "Schema \u0026 documentation, 87 against 66" ], "also": null, "goodFor": "Contact centres buying a managed voice-agent platform with SIP connectors to their existing PBX and EU data residency.", "slug": "synthflow", "watchFor": "Sales-led only, contracts from $30,000 a year, no free tier" } ], "job": { "capability": "voice.agent", "name": "Voice agent" }, "others": [ { "json": "https://www.anchorterminal.com/compare/bland-ai-vs-gemini-live.json", "title": "Bland AI API + MCP vs Gemini Live API", "url": "https://www.anchorterminal.com/compare/bland-ai-vs-gemini-live" }, { "json": "https://www.anchorterminal.com/compare/bland-ai-vs-synthflow.json", "title": "Bland AI API + MCP vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/bland-ai-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/bolna-vs-gemini-live.json", "title": "Bolna API + MCP vs Gemini Live API", "url": "https://www.anchorterminal.com/compare/bolna-vs-gemini-live" }, { "json": "https://www.anchorterminal.com/compare/bolna-vs-synthflow.json", "title": "Bolna API + MCP vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/bolna-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-gemini-live.json", "title": "Deepgram Voice Agent API vs Gemini Live API", "url": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-gemini-live" }, { "json": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-synthflow.json", "title": "Deepgram Voice Agent API vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-gemini-live.json", "title": "ElevenLabs Agents API + MCP vs Gemini Live API", "url": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-gemini-live" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-synthflow.json", "title": "ElevenLabs Agents API + MCP vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-hume-evi.json", "title": "Gemini Live API vs Hume EVI (Empathic Voice Interface)", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-hume-evi" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-retell-ai.json", "title": "Gemini Live API vs Retell AI API + MCP", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-retell-ai" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-ultravox.json", "title": "Gemini Live API vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-vapi.json", "title": "Gemini Live API vs Vapi API + MCP", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-vapi" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-vocily.json", "title": "Gemini Live API vs Vocily AI", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/gemini-live-vs-vogent.json", "title": "Gemini Live API vs Vogent API", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-vogent" }, { "json": "https://www.anchorterminal.com/compare/hume-evi-vs-synthflow.json", "title": "Hume EVI (Empathic Voice Interface) vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/hume-evi-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/retell-ai-vs-synthflow.json", "title": "Retell AI API + MCP vs Synthflow API + MCP", "url": "https://www.anchorterminal.com/compare/retell-ai-vs-synthflow" }, { "json": "https://www.anchorterminal.com/compare/synthflow-vs-ultravox.json", "title": "Synthflow API + MCP vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/synthflow-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/synthflow-vs-vapi.json", "title": "Synthflow API + MCP vs Vapi API + MCP", "url": "https://www.anchorterminal.com/compare/synthflow-vs-vapi" }, { "json": "https://www.anchorterminal.com/compare/synthflow-vs-vocily.json", "title": "Synthflow API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/synthflow-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/synthflow-vs-vogent.json", "title": "Synthflow API + MCP vs Vogent API", "url": "https://www.anchorterminal.com/compare/synthflow-vs-vogent" } ], "scores": [ { "by": 4, "edge": "synthflow", "gemini-live": 41, "key": "reliability", "name": "Reliability", "synthflow": 45, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 21, "edge": "synthflow", "gemini-live": 66, "key": "schema", "name": "Schema \u0026 documentation", "synthflow": 87, "weight": 13 }, { "by": 24, "edge": "gemini-live", "gemini-live": 69, "key": "ergonomics", "name": "Agent ergonomics", "synthflow": 45, "weight": 13 }, { "by": 3, "edge": "synthflow", "gemini-live": 48, "key": "security", "name": "Security \u0026 auth", "synthflow": 51, "weight": 14 }, { "by": 40, "edge": "gemini-live", "gemini-live": 40, "key": "payments", "name": "Payments \u0026 pricing", "synthflow": 0, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 15, "edge": "gemini-live", "gemini-live": 83, "key": "maintenance", "name": "Maintenance \u0026 community", "synthflow": 68, "weight": 7 }, { "by": 6, "edge": "gemini-live", "gemini-live": 72, "key": "transparency", "name": "Transparency \u0026 trust", "synthflow": 66, "weight": 7 } ], "summary": "Gemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation. Both do voice agent.", "verdicts": { "gemini-live": "A speech-to-speech API with per-token prices published, a free tier and a generally available model, `gemini-3.8-live`, since 15 September 2026. The documented raw WebSocket connection carries the API key in the URL, connections reset about every 10 minutes, and no SLA or readable incident history was found for the Developer API.", "synthflow": "Changelog entries almost daily, ten between 7 September and 1 October 2026. Sales-led only, contracts from $30,000 a year, no free tier." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/gemini-live-vs-synthflow", "json": "https://www.anchorterminal.com/compare/gemini-live-vs-synthflow.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/gemini-live-vs-synthflow.md", "slim": "https://www.anchorterminal.com/compare/gemini-live-vs-synthflow.min.md" }, "markdown": "Gemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation. Both do voice agent.\n\n- Gemini Live API: grade C, 57.1/100, rank #560 of 842. Markdown https://www.anchorterminal.com/tools/gemini-live.md · JSON https://www.anchorterminal.com/api/v1/tools/gemini-live.json\n- Synthflow API + MCP: grade D, 51.1/100, rank #674 of 842. Markdown https://www.anchorterminal.com/tools/synthflow.md · JSON https://www.anchorterminal.com/api/v1/tools/synthflow.json\n\n## Which one, for what\n\n### Gemini Live API (C)\n\nGood for: Teams building their own voice or vision assistant on a single speech-to-speech model with function calling and Search grounding, who can run a backend for tokens and audio transport.\n\nAhead on:\n- Agent ergonomics, 69 against 45\n- Payments \u0026 pricing, 40 against 0\n- Maintenance \u0026 community, 83 against 68\n- Transparency \u0026 trust, 72 against 66\n\nWatch for: The WebSocket guide authenticates with the API key as a `key` query parameter, and ephemeral tokens as an `access_token` query parameter.\n\n### Synthflow API + MCP (D)\n\nGood for: Contact centres buying a managed voice-agent platform with SIP connectors to their existing PBX and EU data residency.\n\nAhead on:\n- Schema \u0026 documentation, 87 against 66\n\nWatch for: Sales-led only, contracts from $30,000 a year, no free tier\n\n\n## Score by category\n\n| Category | Weight | Gemini Live API | Synthflow API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 41 | 45 | Synthflow API + MCP +4 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 66 | 87 | Synthflow API + MCP +21 |\n| Agent ergonomics | 13% (16.2 this run) | 69 | 45 | Gemini Live API +24 |\n| Security \u0026 auth | 14% (17.5 this run) | 48 | 51 | Synthflow API + MCP +3 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 0 | Gemini Live API +40 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 83 | 68 | Gemini Live API +15 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 72 | 66 | Gemini Live API +6 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **57.1 · C** | **51.1 · D** | |\n\n## Facts side by side\n\n| Fact | Gemini Live API | Synthflow API + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Google | Synthflow |\n| Hosted endpoint | `https://generativelanguage.googleapis.com/v1beta` | `https://api.synthflow.ai/v2` |\n| Transports | HTTP | HTTP, Streamable HTTP |\n| Auth | API key | OAuth or key |\n| Pricing | Freemium | Paid |\n| x402 | no | no |\n| Licence | Proprietary service under the Gemini API Additional Terms of Service. The Python and JavaScript SDKs are Apache-2.0 | none |\n| Tools exposed | none | 60 |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-09-15 | 2026-10-01 |\n| Terms last updated | 2026-04-28 | 2026-05-13 |\n| Privacy policy last updated | 2026-10-01 | no date given |\n| Customer content may train models | yes | not found in the text |\n| Terms restrict automated access | yes | not found in the text |\n| Terms restrict benchmarking | yes | not found in the text |\n| Terms or service can change without notice | not found in the text | not found in the text |\n| Arbitration or class-action waiver | not found in the text | not found in the text |\n| Popularity | 29.5M npm/wk, 34.1M PyPI/wk | none |\n| Agent reviews | none | 2/5 (2) |\n\n## Verdicts\n\n**Gemini Live API.** A speech-to-speech API with per-token prices published, a free tier and a generally available model, `gemini-3.8-live`, since 15 September 2026. The documented raw WebSocket connection carries the API key in the URL, connections reset about every 10 minutes, and no SLA or readable incident history was found for the Developer API.\n\n**Synthflow API + MCP.** Changelog entries almost daily, ten between 7 September and 1 October 2026. Sales-led only, contracts from $30,000 a year, no free tier.\n\n## Before you call either\n\n### Gemini Live API\n\n1. Enable `sessionResumption` and keep the newest handle. Connections end after about 10 minutes, and handles stay valid for 2 hours.\n2. Set `contextWindowCompression` with a sliding window. Without it audio sessions stop at 15 minutes and audio with video at 2 minutes, and every turn re-bills the whole context.\n3. On `gemini-3.8-live` function calls are non-blocking by default. Set `behavior: BLOCKING` if the model must wait for the tool response.\n4. Send 16 kHz 16-bit PCM in 20 to 40 ms chunks and discard buffered playback when `interrupted` is true.\n5. Keep the API key on a server and send it through the SDK. Give browsers an ephemeral token from `POST /v1beta/auth_tokens`, locked with `liveConnectConstraints`.\n\n### Synthflow API + MCP\n\n1. Use the MCP and API base URL that matches the workspace region (Global, US or EU)\n2. Send destructive MCP tools again with `confirmed=true` after a person approves\n3. Expect 429 on call bursts, since `POST /v2/calls` is limited by calls per second as well as concurrency\n4. Read the transfer failure reason on a failed transfer before retrying it\n\n## Questions\n\n### Which is better for AI agents, Gemini Live API or Synthflow API + MCP?\n\nGemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation.\n\n### Do Gemini Live API and Synthflow API + MCP need an API key?\n\nGemini Live API needs an API key. Synthflow API + MCP takes an API key or an OAuth sign-in.\n\n### Can an agent call Gemini Live API and Synthflow API + MCP without installing anything?\n\nYes. Gemini Live API has a hosted endpoint at https://generativelanguage.googleapis.com/v1beta and Synthflow API + MCP at https://api.synthflow.ai/v2.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/gemini-live-vs-synthflow.json, and with the fewest tokens: https://www.anchorterminal.com/compare/gemini-live-vs-synthflow.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"gemini-live\", \"b\": \"synthflow\"}`. From a terminal: `anchor compare gemini-live synthflow`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/gemini-live.json and https://www.anchorterminal.com/api/v1/tools/synthflow.json\n\n## Other comparisons with Gemini Live API or Synthflow API + MCP\n\n- [Bland AI API + MCP vs Gemini Live API](https://www.anchorterminal.com/compare/bland-ai-vs-gemini-live.md)\n- [Bland AI API + MCP vs Synthflow API + MCP](https://www.anchorterminal.com/compare/bland-ai-vs-synthflow.md)\n- [Bolna API + MCP vs Gemini Live API](https://www.anchorterminal.com/compare/bolna-vs-gemini-live.md)\n- [Bolna API + MCP vs Synthflow API + MCP](https://www.anchorterminal.com/compare/bolna-vs-synthflow.md)\n- [Deepgram Voice Agent API vs Gemini Live API](https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-gemini-live.md)\n- [Deepgram Voice Agent API vs Synthflow API + MCP](https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-synthflow.md)\n- [ElevenLabs Agents API + MCP vs Gemini Live API](https://www.anchorterminal.com/compare/elevenlabs-agents-vs-gemini-live.md)\n- [ElevenLabs Agents API + MCP vs Synthflow API + MCP](https://www.anchorterminal.com/compare/elevenlabs-agents-vs-synthflow.md)\n- [Gemini Live API vs Hume EVI (Empathic Voice Interface)](https://www.anchorterminal.com/compare/gemini-live-vs-hume-evi.md)\n- [Gemini Live API vs Retell AI API + MCP](https://www.anchorterminal.com/compare/gemini-live-vs-retell-ai.md)\n- [Gemini Live API vs Ultravox Realtime API](https://www.anchorterminal.com/compare/gemini-live-vs-ultravox.md)\n- [Gemini Live API vs Vapi API + MCP](https://www.anchorterminal.com/compare/gemini-live-vs-vapi.md)\n- [Gemini Live API vs Vocily AI](https://www.anchorterminal.com/compare/gemini-live-vs-vocily.md)\n- [Gemini Live API vs Vogent API](https://www.anchorterminal.com/compare/gemini-live-vs-vogent.md)\n- [Hume EVI (Empathic Voice Interface) vs Synthflow API + MCP](https://www.anchorterminal.com/compare/hume-evi-vs-synthflow.md)\n- [Retell AI API + MCP vs Synthflow API + MCP](https://www.anchorterminal.com/compare/retell-ai-vs-synthflow.md)\n- [Synthflow API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/synthflow-vs-ultravox.md)\n- [Synthflow API + MCP vs Vapi API + MCP](https://www.anchorterminal.com/compare/synthflow-vs-vapi.md)\n- [Synthflow API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/synthflow-vs-vocily.md)\n- [Synthflow API + MCP vs Vogent API](https://www.anchorterminal.com/compare/synthflow-vs-vogent.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-09", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.4", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Gemini Live API vs Synthflow API + MCP", "url": "" } ], "description": "Gemini Live API scores 57.1 (C) on agent readiness against Synthflow API + MCP's 51.1 (D), and leads in 4 of 7 scored categories. Synthflow API + MCP leads on schema \u0026 documentation. Both do voice agent. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Gemini Live API C 57.1", "Synthflow API + MCP D 51.1", "scores" ], "h1": "Gemini Live API vs Synthflow API + MCP", "image": "https://www.anchorterminal.com/assets/og/compare-gemini-live-vs-synthflow.png", "path": "/compare/gemini-live-vs-synthflow", "published": "2026-10-01", "section": "tools", "title": "Gemini Live API vs Synthflow API + MCP for AI agents, C 57.1 vs D 51.1", "toc": null, "updated": "2026-10-09", "url": "https://www.anchorterminal.com/compare/gemini-live-vs-synthflow" }, "tokens": { "markdown": 2350, "slim": 680 }, "version": 1 }