{ "data": { "a": { "slug": "ultravox", "name": "Ultravox Realtime API", "vendor": "Ultravox (Fixie.ai)", "vendorUrl": "https://www.ultravox.ai", "kind": "http-api", "category": "voice-agents", "summary": "Hosted voice agents on Ultravox, an open-weight model that takes speech directly with no speech-to-text step and answers through a TTS voice.", "url": "https://www.anchorterminal.com/tools/ultravox", "markdownUrl": "https://www.anchorterminal.com/tools/ultravox.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/ultravox.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/ultravox.json", "repo": "https://github.com/fixie-ai/ultravox", "license": "MIT (model code)", "transports": [ "http" ], "remoteUrl": "https://api.ultravox.ai/api", "packages": [ { "registry": "npm", "name": "ultravox-client" }, { "registry": "pypi", "name": "ultravox-client" } ], "auth": "api-key", "authNotes": "`X-API-Key` header on the REST API. Clients join a call with the `joinUrl` returned when it's created, so the key stays on your server.", "pricing": "usage", "pricingNotes": "Pay as you go at $0.05 a minute after 30 free minutes, capped at 5 concurrent calls. Pro is $100 a month (annual rate) at the same $0.05 a minute with no hard concurrency cap, the outbound scheduler, 5 custom voices and 20 RAG corpora. SIP costs 0.5 cents a minute (0.48 on Pro). Threads are $2 per 1M input tokens and $15 per 1M output. Enterprise is custom. Telephony from Twilio or other carriers is billed by them (https://www.ultravox.ai/pricing).", "priceSummary": "$100 / mo", "where": "hosted", "x402": { "level": "no", "evidence": "No x402 support in the docs, pricing page or MCP docs (checked 2026-09-30).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 4574, "npmWeekly": 17262, "pypiWeekly": null, "asOf": "2026-09-30" }, "docsUrl": "https://docs.ultravox.ai", "llmsTxt": "https://docs.ultravox.ai/llms.txt", "openapi": "https://api.ultravox.ai/api/schema/", "capabilities": [ "voice.agent", "voice.speech-to-speech", "voice.tools", "voice.telephony" ], "tags": [ "hosted", "open-weights", "no-card", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming", "speech-to-speech" ], "lastRelease": "2026-07-18", "graded": true, "anchor": { "graded": true, "score": 58.5, "grade": "C", "agentReady": false, "rank": 449, "ranked": true, "rankOf": 722, "categoryRank": 6, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 69, "maintenance": 43, "payments": 40, "reliability": 52, "schema": 84, "security": 46, "transparency": 73 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Flat $0.05 a minute including model and built-in voices. No MCP server.", "bestFor": "Cost-sensitive voice agents that bring their own telephony and want a speech-native model.", "strengths": [ "Flat $0.05 a minute including model and built-in voices", "Speech-native model with no separate STT stage, v0.7 weights public under MIT", "429 and 503 responses with Retry-After and backoff guidance", "Deprecation guide with a minimum 30-day window", "Privacy policy says voice data isn't used for training" ], "weaknesses": [ "No MCP server", "News page, deprecation guide and Python client last updated in December 2025", "Plain API keys with no scopes", "Pay as you go caps at 5 concurrent calls", "No subprocessor list or stated certification" ], "agentNotes": [ "Honour `Retry-After` on 429 and 503 when creating calls", "Pin the model string (`ultravox-v0.7` or `ultravox-v0.6`) rather than relying on the default", "Hand clients the `joinUrl`, never the API key", "Delete calls through the API when you need data removed, there's no retention setting", "Use call stages for multi-step flows instead of one long prompt" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 58.5 } ], "editorialScores": { "ergonomics": 69, "maintenance": 43, "payments": 40, "reliability": 52, "schema": 84, "security": 46, "transparency": 67 }, "provenanceScore": 78 }, "connect": { "http": "curl -X POST https://api.ultravox.ai/api/calls -H \"X-API-Key: $ULTRAVOX_API_KEY\" \\\n -H \"content-type: application/json\" \\\n -d '{\"systemPrompt\":\"You are a friendly receptionist.\",\"voice\":\"Mark\"}'" }, "letme": { "capability": "https://letme.dev/voice.agent", "tool": "https://letme.dev/ultravox" }, "sameCompany": [ "ultravox-voice-cloning" ], "area": "voice", "unitPrices": [ { "item": "Ultravox Realtime", "unit": "call-minute", "usd": 0.05, "note": "model and built-in voices, telephony carrier costs extra" }, { "item": "SIP", "unit": "call-minute", "usd": 0.005, "note": "0.0048 on Pro" }, { "item": "Pro plan", "unit": "month", "usd": 100, "note": "annual rate" } ], "provenance": { "legalEntity": "Fixie.ai Inc.", "domain": "ultravox.ai", "domainRegistered": "2023-10-05", "endpointOnVendorDomain": true, "terms": "https://www.ultravox.ai/terms", "privacy": "https://www.ultravox.ai/privacy", "statusPage": "https://status.ultravox.ai", "changelog": "https://docs.ultravox.ai/changelog/news", "securityTxt": "none", "checked": "2026-09-30", "score": 78 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/ultravox.json", "live": { "slug": "ultravox", "probe": { "target": "https://api.ultravox.ai/api", "method": "get", "lastAt": "2026-10-08T19:53:05.006783423Z", "lastOk": true, "lastStatus": 404, "lastMs": 104, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 112, "p95ms24h": 211, "samples24h": 272, "samples30d": 2143, "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": 225, "ok": 225 } ] }, "vendorStatus": { "page": "https://status.ultravox.ai", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-08T19:39:17.539027262Z" }, "versions": [ { "registry": "github", "name": "fixie-ai/ultravox", "version": "v0.6", "released": "2025-08-18", "seenAt": "2026-10-08T16:33:16.078197385Z" }, { "registry": "npm", "name": "ultravox-client", "version": "0.6.0", "seenAt": "2026-10-08T16:33:14.966022827Z" }, { "registry": "pypi", "name": "ultravox-client", "version": "0.1.0", "released": "2025-12-10", "seenAt": "2026-10-08T16:33:15.890946661Z" } ], "githubStars": 4571, "npmWeekly": 18150, "pypiWeekly": 106, "securityTxt": { "url": "https://ultravox.ai/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-08T15:38:41.355647011Z" }, "llmsTxt": { "url": "https://docs.ultravox.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-08T14:00:59.291054907Z" }, "domain": { "domain": "ultravox.ai", "registered": "2023-10-05", "source": "https://rdap.identitydigital.services/rdap/domain/ultravox.ai", "checkedAt": "2026-10-04T13:04:52.103171331Z" }, "updatedAt": "2026-10-08T19:53:05.006783423Z" } }, "answer": "Ultravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community.", "b": { "slug": "vocily", "name": "Vocily AI", "vendor": "Vocily AI Private Limited", "vendorUrl": "https://vocily.ai", "kind": "http-api", "category": "voice-agents", "summary": "Vocily AI is a hosted voice-agent platform from Bengaluru for phone calls, WhatsApp and website voice and chat, aimed at Indian languages. Its REST API builds and publishes agents, places outbound calls and reads back transcripts, recordings and costs.", "url": "https://www.anchorterminal.com/tools/vocily", "markdownUrl": "https://www.anchorterminal.com/tools/vocily.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/vocily.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/vocily.json", "license": "Proprietary service under Vocily's terms of service. No open-source code or published package was found", "transports": [ "http" ], "remoteUrl": "https://api.vocily.ai", "packages": [], "auth": "api-key", "authNotes": "A Bearer API key (`vk_...`) created in the dashboard under Developers, API Keys, shown once and revocable there. A key is bound to one workspace and reaches the whole public API for it. Billing, team members, account settings and key management answer 403 to any key. Keys have no scopes to configure, although the error table names an `agents:publish` permission for making a version live. Webhooks are signed with HMAC-SHA256 and a timestamp, with two signatures sent during a secret rotation. Access is self-serve after an email-verified signup.", "pricing": "usage", "pricingNotes": "Prepaid wallet with no monthly fee, billed in rupees or US dollars as chosen at signup, each with its own price list. Voice starts at ₹3.10 or $0.041 a connected minute (speech-to-text, model, voice and a $0.03 platform fee), and telephony is free on your own Plivo or VoBiz account or $0.004 a minute in 30-second pulses on a rented number. Chat is charged per model reply from $0.001. A new organisation gets ₹200 or $2 of credit with no card. Ten concurrent calls are included and a pack of two more is $8 a month (https://vocily.ai/pricing).", "priceSummary": "$8 / mo", "where": "hosted", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the docs, the OpenAPI file or the pricing page (checked 2026-10-08).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-10-08" }, "docsUrl": "https://docs.vocily.ai", "llmsTxt": "https://docs.vocily.ai/llms.txt", "openapi": "https://docs.vocily.ai/developers/openapi.json", "capabilities": [ "voice.agent", "voice.pipeline", "voice.tools", "voice.telephony" ], "tags": [ "hosted", "india", "openapi", "llms-txt", "webhooks", "pipeline", "telephony", "whatsapp", "prepaid", "new" ], "lastRelease": "2026-09-30", "graded": true, "anchor": { "graded": true, "score": 53.8, "grade": "D", "agentReady": false, "rank": 540, "ranked": true, "rankOf": 722, "categoryRank": 8, "methodology": "0.4", "run": "2026-10-01", "scores": { "ergonomics": 84, "maintenance": 61, "payments": 40, "reliability": 40, "schema": 90, "security": 46, "transparency": 47 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-08" }, "negative": -5, "negativeNotes": [ "2026-09-23 and 2026-09-25, -3. Two releases removed fields and routes under `/v1` with no notice period, including `tools` on the agent body, `call_type`, `?skip=` and `?offset=`, and the `/widgets` collection routes. The 23 September note says there is no window in which both shapes work. The API reference says fields are never removed or renamed within a version. Documented the same day with migration tables, so the deduction is reduced (https://docs.vocily.ai/developers/changes.md)", "2026-10-08, -2. The developer page on the marketing site lists Fern-generated Python and TypeScript SDKs, an MCP server, API key routes with rotation, webhook endpoint routes, `POST /v1/agents/{id}/chat` and events such as `transcript.ready`. The docs and the OpenAPI file have none of these, keys and webhook endpoints are dashboard-only, and no package was found on npm or PyPI (https://vocily.ai/platform/api-tools and https://docs.vocily.ai/developers/api-reference.md)" ], "verdict": "The REST API is documented in detail for a product a few months old, with an OpenAPI 3.1 file, required idempotency keys on calls, a Retry-After header on 429 and signed webhooks. No status page, SLA, SDK or security programme was found, and two releases in September 2026 removed fields under `/v1` on the day they were announced.", "bestFor": "Indian-language phone agents where a backend builds agents, places outbound calls and reads results over REST, with prepaid rupee billing.", "strengths": [ "OpenAPI 3.1 file with 54 operations, plus llms.txt and a Markdown copy of every docs page", "`POST /v1/calls` requires an `Idempotency-Key`, and a retry returns the original call", "429 responses carry `Retry-After` and `X-RateLimit` headers, with a published limit of 300 requests a minute per key", "Webhooks are signed with HMAC-SHA256 and a timestamp, with a five-minute replay window", "Every component price is public in rupees and US dollars, and signup credit needs no card" ], "weaknesses": [ "No status page, incident history or SLA was found", "Fields and routes were removed under `/v1` on 23 and 25 September 2026 on the day of the announcement", "The marketing site lists SDKs, an MCP server and key management endpoints that the docs don't have", "No security.txt, disclosure policy, bug bounty or certification was found", "The terms and privacy policy name no legal entity, sub-processor or retention period" ], "agentNotes": [ "Send a fresh UUID in `Idempotency-Key` on every `POST /v1/calls`. The API refuses the request without it", "Pass a `from_number` the workspace holds. The shared Test Number returns 403 from the API", "Publish a version and make it live before placing a call, or the call returns 409 `agent_not_published`", "Branch on `detail.code`, falling back to the top-level `code`. A 429 body is flat, so read `Retry-After`", "Read `currency` on every call and chat record. Costs are in rupees or dollars depending on the organisation" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "D", "methodology": "0.4", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 53.8 } ], "editorialScores": { "ergonomics": 84, "maintenance": 61, "payments": 40, "reliability": 40, "schema": 90, "security": 46, "transparency": 34 }, "provenanceScore": 59 }, "connect": { "http": "curl https://api.vocily.ai/v1/agents \\\n -H \"Authorization: Bearer vk_your_key_here\"" }, "letme": { "capability": "https://letme.dev/voice.agent", "tool": "https://letme.dev/vocily" }, "area": "voice", "unitPrices": [ { "item": "Voice, lowest-priced configuration", "unit": "call-minute", "usd": 0.041, "note": "Soniox, GPT-5 Nano, Vocily voice and the $0.03 platform fee. ₹3.10 for a rupee organisation. Telephony extra on a rented number" }, { "item": "Telephony on a number rented from Vocily", "unit": "call-minute", "usd": 0.004, "note": "billed in 30-second pulses, doubled while a transfer is connected. Free on your own carrier account" }, { "item": "Web chat or WhatsApp AI reply, GPT-5 Nano", "unit": "message", "usd": 0.001, "note": "per model reply, up to $0.02 on GPT-5.6 Terra" }, { "item": "WhatsApp utility template, platform fee", "unit": "message", "usd": 0.0004, "note": "Meta's own charges are paid to Meta separately" }, { "item": "Capacity pack, two more concurrent calls", "unit": "month", "usd": 8, "note": "ten concurrent calls are included at no monthly fee" }, { "item": "Rented Indian phone number", "unit": "month", "usd": 5, "note": "₹499 for a rupee organisation" } ], "provenance": { "legalEntity": "VOCILY AI PRIVATE LIMITED", "domain": "vocily.ai", "domainRegistered": "2026-07-12", "domainNote": "RDAP for vocily.ai gives a registration date of 2026-07-12 and VOCILY AI PRIVATE LIMITED as registrant. vocily.com was registered on 2026-01-27 through Squarespace Domains with no registrant shown, and it redirects to vocily.ai. app.vocily.com, which the site links, redirects to app.vocily.ai.", "endpointOnVendorDomain": true, "terms": "https://vocily.ai/terms", "privacy": "https://vocily.ai/privacy", "statusPage": "", "changelog": "https://docs.vocily.ai/developers/changes", "securityTxt": "none", "checked": "2026-10-08", "notes": [ "The terms (last updated 10 June 2026) and the privacy policy (last updated 3 September 2026) refer only to Vocily and name no legal entity, address or governing law. The site footer says Vocily AI, Bengaluru, India. The legal name comes from the registrant field of the vocily.ai domain record.", "The website, the docs (docs.vocily.ai), the API (api.vocily.ai) and the app (app.vocily.ai) are all on vocily.ai. https://vocily.com answers 307 to https://vocily.ai/ and https://app.vocily.com answers 308 to https://app.vocily.ai/.", "No status page was found. status.vocily.ai doesn't resolve and neither the site nor the docs link one.", "https://vocily.ai/.well-known/security.txt and https://vocily.ai/security.txt return 404. The only contact given in the terms and privacy policy is founder@vocily.ai.", "The terms still describe the service as possibly in beta or pre-launch and say paid plans may be introduced later, while the pricing page lists live prices." ], "score": 59 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/vocily.json", "live": { "slug": "vocily", "probe": { "target": "https://api.vocily.ai", "method": "get", "lastAt": "2026-10-08T19:53:06.008514014Z", "lastOk": true, "lastStatus": 200, "lastMs": 554, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 572, "p95ms24h": 651, "samples24h": 27, "samples30d": 27, "days": [ { "date": "2026-10-08", "probes": 27, "ok": 27 } ] }, "pages": [ { "url": "https://docs.vocily.ai/developers/changes", "kind": "changelog", "status": 200, "checkedAt": "2026-10-08T18:19:44.077645596Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "e943bd4b4dc3" }, { "url": "https://vocily.ai/pricing", "kind": "pricing", "status": 200, "checkedAt": "2026-10-08T18:25:39.585046142Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "056eb2694b97" }, { "url": "https://vocily.ai/privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-08T18:25:42.88538991Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "80f0002ad16a" }, { "url": "https://vocily.ai/terms", "kind": "terms", "status": 200, "checkedAt": "2026-10-08T18:25:43.61244357Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "b94cd0abe1e3" } ], "updatedAt": "2026-10-08T19:53:06.008514014Z" } }, "facts": [ { "a": "HTTP API", "b": "HTTP API", "name": "Kind" }, { "a": "Ultravox (Fixie.ai)", "b": "Vocily AI Private Limited", "name": "Vendor" }, { "a": "https://api.ultravox.ai/api", "b": "https://api.vocily.ai", "name": "Hosted endpoint" }, { "a": "HTTP", "b": "HTTP", "name": "Transports" }, { "a": "API key", "b": "API key", "name": "Auth" }, { "a": "Pay per use", "b": "Pay per use", "name": "Pricing" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "MIT (model code)", "b": "Proprietary service under Vocily's terms of service. No open-source code or published package was found", "name": "Licence" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-07-18", "b": "2026-09-30", "name": "Last release" }, { "a": "2026-10-01", "b": "2026-06-10", "name": "Terms last updated" }, { "a": "2026-10-01", "b": "2026-09-03", "name": "Privacy policy last updated" }, { "a": "yes", "b": "not found in the text", "name": "Customer content may train models" }, { "a": "not found in the text", "b": "not found in the text", "name": "Terms restrict automated access" }, { "a": "not found in the text", "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": "4.6k stars, 17k npm/wk", "b": "none", "name": "Popularity" }, { "a": "3/5 (2)", "b": "none", "name": "Agent reviews" } ], "faq": [ { "answer": "Ultravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community.", "question": "Which is better for AI agents, Ultravox Realtime API or Vocily AI?" }, { "answer": "Both need an API key.", "question": "Do Ultravox Realtime API and Vocily AI need an API key?" }, { "answer": "Yes. Ultravox Realtime API has a hosted endpoint at https://api.ultravox.ai/api and Vocily AI at https://api.vocily.ai.", "question": "Can an agent call Ultravox Realtime API and Vocily AI without installing anything?" } ], "goodFor": [ { "aheadOn": [ "Reliability, 52 against 40", "Transparency \u0026 trust, 73 against 47" ], "also": [ "Free to start without a card", "No incidents deducted, where Vocily AI loses 5 points for them" ], "goodFor": "Cost-sensitive voice agents that bring their own telephony and want a speech-native model.", "slug": "ultravox", "watchFor": "No MCP server" }, { "aheadOn": [ "Schema \u0026 documentation, 90 against 84", "Agent ergonomics, 84 against 69", "Maintenance \u0026 community, 61 against 43" ], "also": null, "goodFor": "Indian-language phone agents where a backend builds agents, places outbound calls and reads results over REST, with prepaid rupee billing.", "slug": "vocily", "watchFor": "No status page, incident history or SLA was found" } ], "job": { "capability": "voice.agent", "name": "Voice agent" }, "others": [ { "json": "https://www.anchorterminal.com/compare/bland-ai-vs-ultravox.json", "title": "Bland AI API + MCP vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/bland-ai-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/bland-ai-vs-vocily.json", "title": "Bland AI API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/bland-ai-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/bolna-vs-ultravox.json", "title": "Bolna API + MCP vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/bolna-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/bolna-vs-vocily.json", "title": "Bolna API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/bolna-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-ultravox.json", "title": "Deepgram Voice Agent API vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-vocily.json", "title": "Deepgram Voice Agent API vs Vocily AI", "url": "https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-ultravox.json", "title": "ElevenLabs Agents API + MCP vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-vocily.json", "title": "ElevenLabs Agents API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/elevenlabs-agents-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/hume-evi-vs-ultravox.json", "title": "Hume EVI (Empathic Voice Interface) vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/hume-evi-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/hume-evi-vs-vocily.json", "title": "Hume EVI (Empathic Voice Interface) vs Vocily AI", "url": "https://www.anchorterminal.com/compare/hume-evi-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/retell-ai-vs-ultravox.json", "title": "Retell AI API + MCP vs Ultravox Realtime API", "url": "https://www.anchorterminal.com/compare/retell-ai-vs-ultravox" }, { "json": "https://www.anchorterminal.com/compare/retell-ai-vs-vocily.json", "title": "Retell AI API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/retell-ai-vs-vocily" }, { "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-vocily.json", "title": "Synthflow API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/synthflow-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/ultravox-vs-vapi.json", "title": "Ultravox Realtime API vs Vapi API + MCP", "url": "https://www.anchorterminal.com/compare/ultravox-vs-vapi" }, { "json": "https://www.anchorterminal.com/compare/ultravox-vs-vogent.json", "title": "Ultravox Realtime API vs Vogent API", "url": "https://www.anchorterminal.com/compare/ultravox-vs-vogent" }, { "json": "https://www.anchorterminal.com/compare/vapi-vs-vocily.json", "title": "Vapi API + MCP vs Vocily AI", "url": "https://www.anchorterminal.com/compare/vapi-vs-vocily" }, { "json": "https://www.anchorterminal.com/compare/vocily-vs-vogent.json", "title": "Vocily AI vs Vogent API", "url": "https://www.anchorterminal.com/compare/vocily-vs-vogent" } ], "scores": [ { "by": 12, "edge": "ultravox", "key": "reliability", "name": "Reliability", "ultravox": 52, "vocily": 40, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 6, "edge": "vocily", "key": "schema", "name": "Schema \u0026 documentation", "ultravox": 84, "vocily": 90, "weight": 13 }, { "by": 15, "edge": "vocily", "key": "ergonomics", "name": "Agent ergonomics", "ultravox": 69, "vocily": 84, "weight": 13 }, { "by": 0, "edge": "", "key": "security", "name": "Security \u0026 auth", "ultravox": 46, "vocily": 46, "weight": 14 }, { "by": 0, "edge": "", "key": "payments", "name": "Payments \u0026 pricing", "ultravox": 40, "vocily": 40, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 18, "edge": "vocily", "key": "maintenance", "name": "Maintenance \u0026 community", "ultravox": 43, "vocily": 61, "weight": 7 }, { "by": 26, "edge": "ultravox", "key": "transparency", "name": "Transparency \u0026 trust", "ultravox": 73, "vocily": 47, "weight": 7 } ], "summary": "Ultravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community. Both do voice agent.", "verdicts": { "ultravox": "Flat $0.05 a minute including model and built-in voices. No MCP server.", "vocily": "The REST API is documented in detail for a product a few months old, with an OpenAPI 3.1 file, required idempotency keys on calls, a Retry-After header on 429 and signed webhooks. No status page, SLA, SDK or security programme was found, and two releases in September 2026 removed fields under `/v1` on the day they were announced." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/ultravox-vs-vocily", "json": "https://www.anchorterminal.com/compare/ultravox-vs-vocily.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/ultravox-vs-vocily.md", "slim": "https://www.anchorterminal.com/compare/ultravox-vs-vocily.min.md" }, "markdown": "Ultravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community. Both do voice agent.\n\n- Ultravox Realtime API: grade C, 58.5/100, rank #449 of 722. Markdown https://www.anchorterminal.com/tools/ultravox.md · JSON https://www.anchorterminal.com/api/v1/tools/ultravox.json\n- Vocily AI: grade D, 53.8/100, rank #540 of 722. Markdown https://www.anchorterminal.com/tools/vocily.md · JSON https://www.anchorterminal.com/api/v1/tools/vocily.json\n\n## Which one, for what\n\n### Ultravox Realtime API (C)\n\nGood for: Cost-sensitive voice agents that bring their own telephony and want a speech-native model.\n\nAhead on:\n- Reliability, 52 against 40\n- Transparency \u0026 trust, 73 against 47\n\nAlso in its favour:\n- Free to start without a card\n- No incidents deducted, where Vocily AI loses 5 points for them\n\nWatch for: No MCP server\n\n### Vocily AI (D)\n\nGood for: Indian-language phone agents where a backend builds agents, places outbound calls and reads results over REST, with prepaid rupee billing.\n\nAhead on:\n- Schema \u0026 documentation, 90 against 84\n- Agent ergonomics, 84 against 69\n- Maintenance \u0026 community, 61 against 43\n\nWatch for: No status page, incident history or SLA was found\n\n\n## Score by category\n\n| Category | Weight | Ultravox Realtime API | Vocily AI | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 52 | 40 | Ultravox Realtime API +12 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 84 | 90 | Vocily AI +6 |\n| Agent ergonomics | 13% (16.2 this run) | 69 | 84 | Vocily AI +15 |\n| Security \u0026 auth | 14% (17.5 this run) | 46 | 46 | even |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 40 | even |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 43 | 61 | Vocily AI +18 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 73 | 47 | Ultravox Realtime API +26 |\n| Negative events | ≤15 | 0 | -5 | |\n| **Total** | | **58.5 · C** | **53.8 · D** | |\n\n## Facts side by side\n\n| Fact | Ultravox Realtime API | Vocily AI |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Ultravox (Fixie.ai) | Vocily AI Private Limited |\n| Hosted endpoint | `https://api.ultravox.ai/api` | `https://api.vocily.ai` |\n| Transports | HTTP | HTTP |\n| Auth | API key | API key |\n| Pricing | Pay per use | Pay per use |\n| x402 | no | no |\n| Licence | MIT (model code) | Proprietary service under Vocily's terms of service. No open-source code or published package was found |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-07-18 | 2026-09-30 |\n| Terms last updated | 2026-10-01 | 2026-06-10 |\n| Privacy policy last updated | 2026-10-01 | 2026-09-03 |\n| Customer content may train models | yes | not found in the text |\n| Terms restrict automated access | not found in the text | not found in the text |\n| Terms restrict benchmarking | not found in the text | 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 | 4.6k stars, 17k npm/wk | none |\n| Agent reviews | 3/5 (2) | none |\n\n## Verdicts\n\n**Ultravox Realtime API.** Flat $0.05 a minute including model and built-in voices. No MCP server.\n\n**Vocily AI.** The REST API is documented in detail for a product a few months old, with an OpenAPI 3.1 file, required idempotency keys on calls, a Retry-After header on 429 and signed webhooks. No status page, SLA, SDK or security programme was found, and two releases in September 2026 removed fields under `/v1` on the day they were announced.\n\n## Before you call either\n\n### Ultravox Realtime API\n\n1. Honour `Retry-After` on 429 and 503 when creating calls\n2. Pin the model string (`ultravox-v0.7` or `ultravox-v0.6`) rather than relying on the default\n3. Hand clients the `joinUrl`, never the API key\n4. Delete calls through the API when you need data removed, there's no retention setting\n5. Use call stages for multi-step flows instead of one long prompt\n\n### Vocily AI\n\n1. Send a fresh UUID in `Idempotency-Key` on every `POST /v1/calls`. The API refuses the request without it\n2. Pass a `from_number` the workspace holds. The shared Test Number returns 403 from the API\n3. Publish a version and make it live before placing a call, or the call returns 409 `agent_not_published`\n4. Branch on `detail.code`, falling back to the top-level `code`. A 429 body is flat, so read `Retry-After`\n5. Read `currency` on every call and chat record. Costs are in rupees or dollars depending on the organisation\n\n## Questions\n\n### Which is better for AI agents, Ultravox Realtime API or Vocily AI?\n\nUltravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community.\n\n### Do Ultravox Realtime API and Vocily AI need an API key?\n\nBoth need an API key.\n\n### Can an agent call Ultravox Realtime API and Vocily AI without installing anything?\n\nYes. Ultravox Realtime API has a hosted endpoint at https://api.ultravox.ai/api and Vocily AI at https://api.vocily.ai.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/ultravox-vs-vocily.json, and with the fewest tokens: https://www.anchorterminal.com/compare/ultravox-vs-vocily.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"ultravox\", \"b\": \"vocily\"}`. From a terminal: `anchor compare ultravox vocily`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/ultravox.json and https://www.anchorterminal.com/api/v1/tools/vocily.json\n\n## Other comparisons with Ultravox Realtime API or Vocily AI\n\n- [Bland AI API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/bland-ai-vs-ultravox.md)\n- [Bland AI API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/bland-ai-vs-vocily.md)\n- [Bolna API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/bolna-vs-ultravox.md)\n- [Bolna API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/bolna-vs-vocily.md)\n- [Deepgram Voice Agent API vs Ultravox Realtime API](https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-ultravox.md)\n- [Deepgram Voice Agent API vs Vocily AI](https://www.anchorterminal.com/compare/deepgram-voice-agent-vs-vocily.md)\n- [ElevenLabs Agents API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/elevenlabs-agents-vs-ultravox.md)\n- [ElevenLabs Agents API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/elevenlabs-agents-vs-vocily.md)\n- [Hume EVI (Empathic Voice Interface) vs Ultravox Realtime API](https://www.anchorterminal.com/compare/hume-evi-vs-ultravox.md)\n- [Hume EVI (Empathic Voice Interface) vs Vocily AI](https://www.anchorterminal.com/compare/hume-evi-vs-vocily.md)\n- [Retell AI API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/retell-ai-vs-ultravox.md)\n- [Retell AI API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/retell-ai-vs-vocily.md)\n- [Synthflow API + MCP vs Ultravox Realtime API](https://www.anchorterminal.com/compare/synthflow-vs-ultravox.md)\n- [Synthflow API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/synthflow-vs-vocily.md)\n- [Ultravox Realtime API vs Vapi API + MCP](https://www.anchorterminal.com/compare/ultravox-vs-vapi.md)\n- [Ultravox Realtime API vs Vogent API](https://www.anchorterminal.com/compare/ultravox-vs-vogent.md)\n- [Vapi API + MCP vs Vocily AI](https://www.anchorterminal.com/compare/vapi-vs-vocily.md)\n- [Vocily AI vs Vogent API](https://www.anchorterminal.com/compare/vocily-vs-vogent.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-08", "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": "Ultravox Realtime API vs Vocily AI", "url": "" } ], "description": "Ultravox Realtime API scores 58.5 (C) on agent readiness against Vocily AI's 53.8 (D), and leads in 2 of 7 scored categories. Vocily AI leads on schema \u0026 documentation, agent ergonomics and maintenance \u0026 community. Both do voice agent. Category scores, facts, verdicts and agent…", "facts": [ "Ultravox Realtime API C 58.5", "Vocily AI D 53.8", "scores" ], "h1": "Ultravox Realtime API vs Vocily AI", "image": "https://www.anchorterminal.com/assets/og/compare-ultravox-vs-vocily.png", "path": "/compare/ultravox-vs-vocily", "published": "2026-10-01", "section": "tools", "title": "Ultravox Realtime API vs Vocily AI for AI agents, C 58.5 vs D 53.8", "toc": null, "updated": "2026-10-08", "url": "https://www.anchorterminal.com/compare/ultravox-vs-vocily" }, "tokens": { "markdown": 2150, "slim": 630 }, "version": 1 }