{ "data": { "a": { "slug": "twilio-voice", "name": "Twilio Programmable Voice API + MCP", "vendor": "Twilio", "vendorUrl": "https://www.twilio.com", "kind": "http-api", "category": "voice-calling", "summary": "Programmable Voice for placing and answering calls on Twilio numbers in 100+ countries, controlled with TwiML or REST.", "url": "https://www.anchorterminal.com/tools/twilio-voice", "markdownUrl": "https://www.anchorterminal.com/tools/twilio-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/twilio-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/twilio-voice.json", "repo": "https://github.com/twilio-labs/mcp", "license": "MIT", "transports": [ "http", "streamable-http", "stdio" ], "remoteUrl": "https://api.twilio.com/2010-04-01", "packages": [ { "registry": "npm", "name": "twilio" }, { "registry": "pypi", "name": "twilio" }, { "registry": "npm", "name": "@twilio-alpha/mcp" } ], "auth": "mixed", "authNotes": "HTTP Basic auth with the Account SID and Auth Token, or an API key SID and secret (recommended). Webhooks and Media Streams or ConversationRelay websocket connections carry an `X-Twilio-Signature` to validate. The hosted docs MCP needs no credentials. The local alpha MCP takes `ACCOUNT_SID/API_KEY:API_SECRET` as a command-line argument.", "pricing": "usage", "pricingNotes": "Pay as you go, per minute. US outbound $0.014 a minute, inbound $0.0085 on local numbers and $0.022 on toll-free. Local numbers $1.15 a month, toll-free $2.15. Media Streams $0.0044 a minute, ConversationRelay $0.07 a minute, SIP interface and browser or app calls $0.004 a minute, recording $0.0025 a minute plus $0.0005 a minute a month storage, transcription $0.05 a minute, answering machine detection $0.0075 a call. The trial needs no card and gives free units, including 75 voice minutes, for 30 days (https://www.twilio.com/en-us/voice/pricing/us, https://www.twilio.com/docs/usage/tutorials/how-to-use-your-free-trial-account).", "priceSummary": "$1.15 / mo", "where": "both", "x402": { "level": "no", "evidence": "No x402 support in docs, pricing or MCP README (checked 2026-09-30).", "endpoints": [] }, "toolCount": 2, "popularity": { "githubStars": 111, "npmWeekly": 7213599, "pypiWeekly": 4834611, "asOf": "2026-09-30" }, "docsUrl": "https://www.twilio.com/docs/voice", "llmsTxt": "https://www.twilio.com/docs/llms.txt", "openapi": "https://raw.githubusercontent.com/twilio/twilio-oai/main/spec/json/twilio_api_v2010.json", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "no-card", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming", "enterprise" ], "lastRelease": "2026-09-28", "graded": true, "anchor": { "graded": true, "score": 80.4, "grade": "A", "agentReady": true, "rank": 6, "ranked": true, "rankOf": 452, "categoryRank": 1, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 80, "maintenance": 85, "payments": 40, "reliability": 90, "schema": 92, "security": 85, "transparency": 81 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Twilio APIs SLA at 99.95 per cent for every paying customer, with 10 per cent credits. US outbound at $0.014 a minute, plus $0.0044 for Media Streams or $0.07 for ConversationRelay.", "strengths": [ "Twilio APIs SLA at 99.95 per cent for every paying customer, with 10 per cent credits", "Restricted API keys with up to 100 endpoint permissions each", "Public OpenAPI specs, llms.txt with Markdown twins, and a numbered error dictionary", "No-card trial with 75 free voice minutes for 30 days", "twilio-node released three times in the last 90 days, most recently 6.1.2 on 2026-09-28" ], "weaknesses": [ "US outbound at $0.014 a minute, plus $0.0044 for Media Streams or $0.07 for ConversationRelay", "1 outbound call a second per account by default", "No idempotency key on call creation", "The MCP that can place calls is an alpha last published in July 2025, and the hosted one only searches docs", "No security.txt on twilio.com" ], "agentNotes": [ "Use `\u003cConnect\u003e\u003cStream\u003e` for two-way audio. It blocks further TwiML until the websocket closes", "Use `\u003cConnect\u003e\u003cConversationRelay\u003e` when you only want to handle text, and set `interruptible` for barge-in", "Trial calls reach only verified numbers in your sign-up country", "Retry a 429 with backoff, but check the Calls list before retrying a create that timed out, since there's no idempotency key", "Validate `X-Twilio-Signature` on every webhook and websocket upgrade" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 8, "avgRating": 3.1, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "A", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 80.4 } ], "editorialScores": { "ergonomics": 80, "maintenance": 85, "payments": 40, "reliability": 90, "schema": 92, "security": 85, "transparency": 72 }, "provenanceScore": 90 }, "connect": { "http": "curl -X POST \"https://api.twilio.com/2010-04-01/Accounts/$TWILIO_ACCOUNT_SID/Calls.json\" \\\n -u \"$TWILIO_API_KEY:$TWILIO_API_SECRET\" \\\n --data-urlencode \"To=+15558675310\" --data-urlencode \"From=+15017122661\" \\\n --data-urlencode \"Twiml=\u003cResponse\u003e\u003cSay\u003eHello from Twilio\u003c/Say\u003e\u003c/Response\u003e\"", "claudeCode": "claude mcp add --transport http twilio-docs https://mcp.twilio.com/docs", "config": { "mcpServers": { "twilio": { "args": [ "-y", "@twilio-alpha/mcp", "${TWILIO_ACCOUNT_SID}/${TWILIO_API_KEY}:${TWILIO_API_SECRET}", "--services", "twilio_api_v2010" ], "command": "npx" } } } }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/twilio-voice" }, "sameCompany": [ "stytch-connected-apps", "sendgrid", "twilio" ], "area": "voice", "unitPrices": [ { "item": "Outbound call, US", "unit": "call-minute", "usd": 0.014, "note": "local or toll-free destinations" }, { "item": "Inbound call, US local number", "unit": "call-minute", "usd": 0.0085 }, { "item": "Inbound call, US toll-free number", "unit": "call-minute", "usd": 0.022 }, { "item": "US local number", "unit": "month", "usd": 1.15 }, { "item": "US toll-free number", "unit": "month", "usd": 2.15 }, { "item": "Media Streams", "unit": "call-minute", "usd": 0.0044, "note": "on top of call minutes" }, { "item": "ConversationRelay", "unit": "call-minute", "usd": 0.07, "note": "on top of call minutes" }, { "item": "Call recording", "unit": "call-minute", "usd": 0.0025 } ], "provenance": { "legalEntity": "Twilio Inc.", "domain": "twilio.com", "domainRegistered": "2007-10-26", "endpointOnVendorDomain": true, "terms": "https://www.twilio.com/en-us/legal/tos", "privacy": "https://www.twilio.com/en-us/legal/privacy", "statusPage": "https://status.twilio.com", "changelog": "https://www.twilio.com/en-us/changelog", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "The terms also name Twilio Ireland Limited for customers outside the US." ], "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/twilio-voice.json", "live": { "slug": "twilio-voice", "probe": { "target": "https://api.twilio.com/2010-04-01", "method": "get", "lastAt": "2026-10-05T00:25:51.264031827Z", "lastOk": true, "lastStatus": 200, "lastMs": 31, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 27, "p95ms24h": 66, "samples24h": 272, "samples30d": 1107, "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": 5, "ok": 5 } ] }, "vendorStatus": { "page": "https://status.twilio.com", "indicator": "minor", "summary": "Partially Degraded Service", "checkedAt": "2026-10-05T00:23:03.539915696Z" }, "versions": [ { "registry": "github", "name": "twilio-labs/mcp", "version": "0.0.3", "released": "2025-03-25", "seenAt": "2026-10-04T16:42:28.341727729Z" }, { "registry": "npm", "name": "@twilio-alpha/mcp", "version": "0.7.0", "seenAt": "2026-10-04T16:42:26.54293887Z" }, { "registry": "npm", "name": "twilio", "version": "6.1.2", "seenAt": "2026-10-04T16:42:26.104679108Z" }, { "registry": "pypi", "name": "twilio", "version": "9.11.2", "released": "2026-09-28", "seenAt": "2026-10-04T16:42:26.381954279Z" } ], "githubStars": 112, "npmWeekly": 7817134, "pypiWeekly": 5153208, "securityTxt": { "url": "https://twilio.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:15:43.282608786Z" }, "llmsTxt": { "url": "https://www.twilio.com/docs/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:18:18.461750128Z" }, "domain": { "domain": "twilio.com", "registered": "2007-10-26", "source": "https://rdap.verisign.com/com/v1/domain/twilio.com", "checkedAt": "2026-10-04T13:05:12.523190086Z" }, "pages": [ { "url": "https://www.twilio.com/en-us/voice/pricing/us", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:52:42.057003458Z", "changedAt": "2026-10-03T15:40:33.277161645Z", "fingerprint": "870f6e38fa5f" } ], "updatedAt": "2026-10-05T00:25:51.264031827Z" } }, "b": { "slug": "vonage-voice", "name": "Vonage Voice API + MCP", "vendor": "Vonage (Ericsson)", "vendorUrl": "https://www.vonage.com", "kind": "http-api", "category": "voice-calling", "summary": "Voice API that controls calls with NCCO, a JSON list of actions such as talk, input, record, connect and transfer.", "url": "https://www.anchorterminal.com/tools/vonage-voice", "markdownUrl": "https://www.anchorterminal.com/tools/vonage-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/vonage-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/vonage-voice.json", "transports": [ "http", "stdio", "streamable-http" ], "remoteUrl": "https://api.nexmo.com/v1", "packages": [ { "registry": "npm", "name": "@vonage/server-sdk" }, { "registry": "pypi", "name": "vonage" }, { "registry": "npm", "name": "@vonage/vonage-mcp-server-api-bindings" } ], "auth": "mixed", "authNotes": "The Voice API takes a Vonage Application JWT signed RS256 with the application's private key. Signed webhooks carry an HS256 JWT to verify with the signature secret. The MCP server reads the API key, secret, application ID and a base64 private key from env vars.", "pricing": "usage", "pricingNotes": "Pay as you go, billed per second. US outbound $0.01446 a minute, inbound $0.00495 on local numbers and $0.0154 on toll-free. Calls to or from SIP, in-app (WebRTC) and websocket endpoints $0.00492 a minute. US numbers €1.81 a month. New accounts get test credit with no card. Rates are from Vonage's downloadable pricing sheet, since the pricing page blocks automated requests (https://www.vonage.com/communications-apis/voice/pricing/).", "priceSummary": "Pay per use", "where": "both", "x402": { "level": "no", "evidence": "No x402 support in docs, pricing or MCP README (checked 2026-09-30).", "endpoints": [] }, "toolCount": 14, "popularity": { "githubStars": null, "npmWeekly": 154249, "pypiWeekly": 67062, "asOf": "2026-09-30" }, "docsUrl": "https://developer.vonage.com/en/voice/voice-api/overview", "llmsTxt": "https://developer.vonage.com/llms.txt", "openapi": "https://developer.vonage.com/api/v1/developer/api/file/voice?format=json", "registryName": "io.github.Vonage/vonage-documentation-mcp", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "no-card", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming", "enterprise" ], "lastRelease": "2026-09-16", "graded": true, "anchor": { "graded": true, "score": 59.1, "grade": "C", "agentReady": false, "rank": 270, "ranked": true, "rankOf": 452, "categoryRank": 8, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 60, "maintenance": 78, "payments": 35, "reliability": 45, "schema": 88, "security": 60, "transparency": 50 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "low", "date": "2026-10-01" }, "negative": 0, "verdict": "Websocket audio as 16-bit linear PCM at 8, 16 or 24 kHz, both directions. First call needs an application, a private key and a signed JWT.", "strengths": [ "Websocket audio as 16-bit linear PCM at 8, 16 or 24 kHz, both directions", "Per-second billing on every call", "Short-lived application JWTs whose ACLs can limit a token to named paths and methods, and signed webhooks with a body hash", "OpenAPI spec and an llms.txt that tells agents which hosts to use", "€2 test credit without a card" ], "weaknesses": [ "First call needs an application, a private key and a signed JWT", "No Voice API rate limit or SLA found, and the error catalogue's throttling advice is to wait an amount that differs per API", "Pricing page returns 403 to automated requests, rates live in a spreadsheet", "MCP server has no tools for live call control, only a one-way voice message", "No security.txt, and the API runs on the legacy nexmo.com domain" ], "agentNotes": [ "Generate a short-lived JWT with an ACL limited to the call paths the agent needs, and keep the private key out of prompts", "Use a `connect` action with a websocket endpoint and `audio/l16;rate=16000` for speech models", "Keep the api.nexmo.com hostname, Vonage's llms.txt says not to swap it", "Enable signed webhooks and verify the HS256 JWT on each event", "Expect RFC 7807 errors (`type`, `title`, `detail`, `instance`) and back off on a throttling error, since no Voice rate limit is published" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 2.5, "history": [ { "basis": "public evidence", "confidence": "low", "grade": "C", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 59.1 } ], "editorialScores": { "ergonomics": 60, "maintenance": 78, "payments": 35, "reliability": 45, "schema": 88, "security": 60, "transparency": 25 }, "provenanceScore": 75 }, "connect": { "http": "curl -X POST https://api.nexmo.com/v1/calls -H \"Authorization: Bearer $VONAGE_JWT\" \\\n -H \"Content-Type: application/json\" \\\n -d '{\"to\":[{\"type\":\"phone\",\"number\":\"14155550100\"}],\"from\":{\"type\":\"phone\",\"number\":\"14155550101\"},\"ncco\":[{\"action\":\"talk\",\"text\":\"Hello from Vonage\"}]}'", "claudeCode": "claude mcp add --transport http vonage-docs https://documentation-mcp.vonage.dev/mcp", "config": { "mcpServers": { "vonage": { "args": [ "-y", "@vonage/vonage-mcp-server-api-bindings" ], "command": "npx", "env": { "VONAGE_API_KEY": "${VONAGE_API_KEY}", "VONAGE_API_SECRET": "${VONAGE_API_SECRET}", "VONAGE_APPLICATION_ID": "${VONAGE_APPLICATION_ID}", "VONAGE_PRIVATE_KEY64": "${VONAGE_PRIVATE_KEY64}", "VONAGE_VIRTUAL_NUMBER": "${VONAGE_VIRTUAL_NUMBER}" } } } } }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/vonage-voice" }, "sameCompany": [ "vonage" ], "area": "voice", "unitPrices": [ { "item": "Outbound call, US", "unit": "call-minute", "usd": 0.01446, "note": "billed per second" }, { "item": "Inbound call, US local number", "unit": "call-minute", "usd": 0.00495, "note": "billed per second" }, { "item": "Inbound call, US toll-free number", "unit": "call-minute", "usd": 0.0154 }, { "item": "Websocket, SIP or in-app leg", "unit": "call-minute", "usd": 0.00492 } ], "provenance": { "legalEntity": "Vonage Holdings Corp.", "domain": "vonage.com", "domainRegistered": "2000-12-12", "domainNote": "The API endpoints sit on the legacy nexmo.com domain, from Nexmo's acquisition in 2016.", "endpointOnVendorDomain": false, "terms": "https://www.vonage.com/legal/communications-apis/terms-of-use/", "privacy": "https://www.vonage.com/legal/privacy-policy/", "statusPage": "https://vonageapi.statuspage.io", "changelog": "https://developer.vonage.com/en/changelogs", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "The privacy notice names Vonage Holdings Corp. as controller where one entity applies. The API terms set the contracting entity by customer region in Schedule 1, which we couldn't read because vonage.com returned 403 to automated requests." ], "score": 75 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/vonage-voice.json", "live": { "slug": "vonage-voice", "probe": { "target": "https://api.nexmo.com/v1", "method": "get", "lastAt": "2026-10-05T00:25:52.167202594Z", "lastOk": true, "lastStatus": 404, "lastMs": 48, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 56, "p95ms24h": 89, "samples24h": 272, "samples30d": 1107, "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": 5, "ok": 5 } ] }, "vendorStatus": { "page": "https://vonageapi.statuspage.io", "indicator": "minor", "summary": "Partially Degraded Service", "checkedAt": "2026-10-05T00:23:03.780768253Z" }, "versions": [ { "registry": "npm", "name": "@vonage/server-sdk", "version": "3.30.1", "seenAt": "2026-10-04T16:43:40.029661946Z" }, { "registry": "npm", "name": "@vonage/vonage-mcp-server-api-bindings", "version": "1.5.1", "seenAt": "2026-10-04T16:43:42.417836886Z" }, { "registry": "pypi", "name": "vonage", "version": "4.9.0", "released": "2026-09-16", "seenAt": "2026-10-04T16:43:42.228896026Z" } ], "npmWeekly": 152256, "pypiWeekly": 69501, "securityTxt": { "url": "https://vonage.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:15:53.518357179Z" }, "llmsTxt": { "url": "https://developer.vonage.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:18:21.395540221Z" }, "domain": { "domain": "vonage.com", "registered": "2000-12-12", "source": "https://rdap.verisign.com/com/v1/domain/vonage.com", "checkedAt": "2026-10-04T13:04:15.703583171Z" }, "pages": [ { "url": "https://developer.vonage.com/en/changelogs", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:42:39.187027625Z", "changedAt": "2026-10-02T15:19:02.626368872Z", "fingerprint": "81bb42dd9db6" }, { "url": "https://www.vonage.com/communications-apis/voice/pricing/", "kind": "pricing", "status": 304, "checkedAt": "2026-10-04T15:52:50.243045792Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "efeb31a58cfc" }, { "url": "https://www.vonage.com/legal/privacy-policy/", "kind": "privacy", "status": 304, "checkedAt": "2026-10-04T15:52:54.218403359Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "ef11a28348cd" }, { "url": "https://www.vonage.com/legal/communications-apis/terms-of-use/", "kind": "terms", "status": 304, "checkedAt": "2026-10-04T15:52:52.203108406Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "004c80c35ffa" } ], "updatedAt": "2026-10-05T00:25:52.167202594Z" } }, "summary": "Twilio Programmable Voice API + MCP has a score of 80.4 (A) against Vonage Voice API + MCP's 59.1 (C). Both do voice calls. The largest gap is reliability, 45 points." }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice", "json": "https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice.md", "slim": "https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice.min.md" }, "markdown": "Twilio Programmable Voice API + MCP has a score of 80.4 (A) against Vonage Voice API + MCP's 59.1 (C). Both do voice calls. The largest gap is reliability, 45 points.\n\n- Twilio Programmable Voice API + MCP: grade A, 80.4/100, rank #6 of 452. Markdown https://www.anchorterminal.com/tools/twilio-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/twilio-voice.json\n- Vonage Voice API + MCP: grade C, 59.1/100, rank #270 of 452. Markdown https://www.anchorterminal.com/tools/vonage-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/vonage-voice.json\n\n## Which one, for what\n\nPick Twilio Programmable Voice API + MCP for reliability (+45), agent ergonomics (+20), security \u0026 auth (+25), payments \u0026 pricing (+5), maintenance \u0026 community (+7), transparency \u0026 trust (+31).\n\nPick Vonage Voice API + MCP for nothing in particular (no category where it leads by five points or more).\n\n## Score by category\n\n| Category | Weight | Twilio Programmable Voice API + MCP | Vonage Voice API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 90 | 45 | Twilio Programmable Voice API + MCP +45 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 92 | 88 | Twilio Programmable Voice API + MCP +4 |\n| Agent ergonomics | 13% (16.2 this run) | 80 | 60 | Twilio Programmable Voice API + MCP +20 |\n| Security \u0026 auth | 14% (17.5 this run) | 85 | 60 | Twilio Programmable Voice API + MCP +25 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 40 | 35 | Twilio Programmable Voice API + MCP +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 85 | 78 | Twilio Programmable Voice API + MCP +7 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 81 | 50 | Twilio Programmable Voice API + MCP +31 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **80.4 · A** | **59.1 · C** | |\n\n## Facts side by side\n\n| Fact | Twilio Programmable Voice API + MCP | Vonage Voice API + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Twilio | Vonage (Ericsson) |\n| Hosted endpoint | `https://api.twilio.com/2010-04-01` | `https://api.nexmo.com/v1` |\n| Transports | HTTP, Streamable HTTP, stdio | HTTP, stdio, Streamable HTTP |\n| Auth | OAuth or key | OAuth or key |\n| Pricing | Pay per use | Pay per use |\n| x402 | no | no |\n| Licence | MIT | none |\n| Tools exposed | 2 | 14 |\n| Context cost (tools/list) | n/a | n/a |\n| p95 latency | not measured yet | not measured yet |\n| Availability (30d) | not measured yet | not measured yet |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| MCP registry | not listed | `io.github.Vonage/vonage-documentation-mcp` |\n| Last release | 2026-09-28 | 2026-09-16 |\n| Popularity | 111 stars, 7.2M npm/wk, 4.8M PyPI/wk | 154k npm/wk, 67k PyPI/wk |\n| Agent reviews | 3.1/5 (8) | 2.5/5 (2) |\n\n## Verdicts\n\n**Twilio Programmable Voice API + MCP.** Twilio APIs SLA at 99.95 per cent for every paying customer, with 10 per cent credits. US outbound at $0.014 a minute, plus $0.0044 for Media Streams or $0.07 for ConversationRelay.\n\n**Vonage Voice API + MCP.** Websocket audio as 16-bit linear PCM at 8, 16 or 24 kHz, both directions. First call needs an application, a private key and a signed JWT.\n\n## Before you call either\n\n### Twilio Programmable Voice API + MCP\n\n1. Use `\u003cConnect\u003e\u003cStream\u003e` for two-way audio. It blocks further TwiML until the websocket closes\n2. Use `\u003cConnect\u003e\u003cConversationRelay\u003e` when you only want to handle text, and set `interruptible` for barge-in\n3. Trial calls reach only verified numbers in your sign-up country\n4. Retry a 429 with backoff, but check the Calls list before retrying a create that timed out, since there's no idempotency key\n5. Validate `X-Twilio-Signature` on every webhook and websocket upgrade\n\n### Vonage Voice API + MCP\n\n1. Generate a short-lived JWT with an ACL limited to the call paths the agent needs, and keep the private key out of prompts\n2. Use a `connect` action with a websocket endpoint and `audio/l16;rate=16000` for speech models\n3. Keep the api.nexmo.com hostname, Vonage's llms.txt says not to swap it\n4. Enable signed webhooks and verify the HS256 JWT on each event\n5. Expect RFC 7807 errors (`type`, `title`, `detail`, `instance`) and back off on a throttling error, since no Voice rate limit is published\n\n## Other comparisons with Twilio Programmable Voice API + MCP or Vonage Voice API + MCP\n\n- [Bandwidth Voice API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-twilio-voice.md)\n- [Bandwidth Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-vonage-voice.md)\n- [Exotel Voice API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/exotel-voice-vs-twilio-voice.md)\n- [Exotel Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/exotel-voice-vs-vonage-voice.md)\n- [Infobip Calls API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/infobip-calls-vs-twilio-voice.md)\n- [Infobip Calls API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/infobip-calls-vs-vonage-voice.md)\n- [Plivo Voice API vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/plivo-voice-vs-twilio-voice.md)\n- [Plivo Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/plivo-voice-vs-vonage-voice.md)\n- [SignalWire Voice API vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-twilio-voice.md)\n- [SignalWire Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-vonage-voice.md)\n- [Sinch Voice API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/sinch-voice-vs-twilio-voice.md)\n- [Sinch Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/sinch-voice-vs-vonage-voice.md)\n- [Telnyx Voice API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/telnyx-voice-vs-twilio-voice.md)\n- [Telnyx Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/telnyx-voice-vs-vonage-voice.md)\n- [Twilio Programmable Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/twilio-voice-vs-voximplant.md)\n- [Vonage Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/vonage-voice-vs-voximplant.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-05", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.3", "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": "Twilio Programmable Voice API + MCP vs Vonage Voice API + MCP", "url": "" } ], "description": "Twilio Programmable Voice API + MCP has a score of 80.4 (A) against Vonage Voice API + MCP's 59.1 (C). Both do voice calls. The largest gap is reliability, 45 points. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Twilio Programmable Voice API + MCP A 80.4", "Vonage Voice API + MCP C 59.1", "scores" ], "h1": "Twilio Programmable Voice API + MCP vs Vonage Voice API + MCP", "image": "https://www.anchorterminal.com/assets/og/compare-twilio-voice-vs-vonage-voice.png", "path": "/compare/twilio-voice-vs-vonage-voice", "published": "2026-10-01", "section": "tools", "title": "Twilio Programmable Voice API + MCP vs Vonage Voice API + MCP", "toc": null, "updated": "2026-10-05", "url": "https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice" }, "tokens": { "markdown": 1800, "slim": 380 }, "version": 1 }