{ "data": { "a": { "slug": "sinch-voice", "name": "Sinch Voice API + MCP", "vendor": "Sinch", "vendorUrl": "https://sinch.com", "kind": "http-api", "category": "voice-calling", "summary": "Programmable voice over PSTN, SIP and WebSocket streams, driven by SVAML call-control JSON.", "url": "https://www.anchorterminal.com/tools/sinch-voice", "markdownUrl": "https://www.anchorterminal.com/tools/sinch-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/sinch-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/sinch-voice.json", "repo": "https://github.com/sinch/sinch-mcp-server", "license": "Apache-2.0", "transports": [ "http", "stdio", "streamable-http" ], "remoteUrl": "https://voice.api.sinch.com/v2", "packages": [ { "registry": "npm", "name": "@sinch/sdk-core" }, { "registry": "pypi", "name": "sinch" }, { "registry": "npm", "name": "@sinch/mcp" } ], "auth": "mixed", "authNotes": "Voice API v2 uses a project access key and secret, over Basic auth or as an OAuth 2.0 token. Voice API v1 at calling.api.sinch.com uses an application key and secret with Basic auth or signed requests, and Sinch recommends signed requests in production. Webhooks can be signed.", "pricing": "usage", "pricingNotes": "Prepaid pay as you go for self-created accounts, with test credits on signup. The downloadable price list gives US outbound at $0.01 a minute, billed in 60-second increments. The pricing page only shows illustrative inbound, SIP, recording and number prices (for example inbound $0.008 a minute and a number at $0.80 a month plus $0.80 setup), so check your dashboard before relying on them. TTS, conferences and IVR menus carry no extra charge (https://sinch.com/pricing/voice/).", "priceSummary": "Pay per use", "where": "both", "x402": { "level": "no", "evidence": "No x402 or stablecoin payment path in the voice docs, pricing or llms.txt (checked 2026-09-30).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 1, "npmWeekly": 15648, "pypiWeekly": 11166, "asOf": "2026-09-30" }, "docsUrl": "https://developers.sinch.com/docs/voice-2.0/overview", "llmsTxt": "https://developers.sinch.com/llms.txt", "openapi": "https://developers.sinch.com/_bundle/docs/voice-2.0/api-reference/voice.yaml", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "mcp", "llms-txt", "typescript", "python", "webhooks", "streaming", "batch" ], "lastRelease": "2026-09-23", "graded": true, "anchor": { "graded": true, "score": 62.8, "grade": "B", "agentReady": false, "rank": 212, "ranked": true, "rankOf": 452, "categoryRank": 5, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 81, "maintenance": 79, "payments": 35, "reliability": 52, "schema": 79, "security": 50, "transparency": 73 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "Voice API v2 with bidirectional PCM streams and a text relay that handles barge-in. Two API generations with different hosts, auth and markup, and v1 release notes stop in 2022.", "strengths": [ "Voice API v2 with bidirectional PCM streams and a text relay that handles barge-in", "Idempotency-Key on v2 call, batch and service writes, with a 10-minute replay window", "OpenAPI file for v2, and official SDKs in four languages, with v2 in Node 1.6.0 and Python 2.2.0 since September", "Signed callbacks in v1 and v2, and OAuth 2.0 tokens on v2", "Test credits and a test number on signup without a card, and ISO 27001 and SOC 2 Type II" ], "weaknesses": [ "Two API generations with different hosts, auth and markup, and v1 release notes stop in 2022", "No published voice rate limits or SLA, and 429 handling is described only in SDK changelogs", "Public pricing is a spreadsheet download plus illustrative examples", "The voice MCP is an alpha (0.0.1-alpha.6) that can't stream audio", "No security.txt or bug bounty" ], "agentNotes": [ "Start new work on Voice API v2 at voice.api.sinch.com. v1 is the older callout model", "Send an Idempotency-Key (a UUID v4) on v2 call, batch and service writes, and reuse it when you retry within 10 minutes", "Use the MCP tts-callout tool for one-off spoken notifications, and the REST API for anything that streams audio", "Trial accounts dial verified numbers only, one call at a time, so verify the test handset first", "Verify the webhook signature and deduplicate on `ce-id` and `ce-source`, since fallback delivery can repeat events" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 62.8 } ], "editorialScores": { "ergonomics": 81, "maintenance": 79, "payments": 35, "reliability": 52, "schema": 79, "security": 50, "transparency": 55 }, "provenanceScore": 90 }, "connect": { "http": "curl -X POST \"https://voice.api.sinch.com/v2/projects/$SINCH_PROJECT_ID/calls\" -u \"$SINCH_KEY_ID:$SINCH_KEY_SECRET\" \\\n -H \"Content-Type: application/json\" -d '{\"commands\":[{\"command\":\"dial\",\"callName\":\"origin\",\"from\":{\"type\":\"PHONE\",\"phone\":{\"number\":\"+15551234567\"}},\"to\":{\"type\":\"PHONE\",\"phone\":{\"number\":\"+15559876543\"}},\"events\":{\"onAnswer\":[{\"command\":\"messages\",\"messages\":[{\"type\":\"SAY\",\"say\":{\"text\":\"Hello from Sinch\"}}]}]}}]}'", "config": { "mcpServers": { "sinch": { "args": [ "-y", "@sinch/mcp" ], "command": "npx", "env": { "APPLICATION_KEY": "${SINCH_APP_KEY}", "APPLICATION_SECRET": "${SINCH_APP_SECRET}", "CALLING_LINE_IDENTIFICATION": "${SINCH_CLI_NUMBER}", "KEY_ID": "${SINCH_KEY_ID}", "KEY_SECRET": "${SINCH_KEY_SECRET}", "PROJECT_ID": "${SINCH_PROJECT_ID}" } } } } }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/sinch-voice" }, "sameCompany": [ "sinch" ], "area": "voice", "unitPrices": [ { "item": "US outbound", "unit": "call-minute", "usd": 0.01, "note": "outbound to US numbers, 60-second increments, from the downloadable price list" } ], "provenance": { "legalEntity": "Sinch AB (publ)", "domain": "sinch.com", "domainRegistered": "1997-12-03", "endpointOnVendorDomain": true, "terms": "https://sinch.com/legal/terms-and-conditions/other-sinch-terms-conditions/general-terms-and-conditions/", "privacy": "https://sinch.com/legal/privacy-notice/", "statusPage": "https://status.sinch.com", "changelog": "https://developers.sinch.com/docs/voice/release-notes", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "Provenance shared with the Sinch messaging listing. The general terms name the contracting Sinch entity only in the order form, Sinch AB (publ) is the listed parent.", "The v1 voice release notes were last updated on 2022-10-06." ], "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/sinch-voice.json", "live": { "slug": "sinch-voice", "probe": { "target": "https://voice.api.sinch.com/v2", "method": "get", "lastAt": "2026-10-04T23:48:15.890085803Z", "lastOk": true, "lastStatus": 404, "lastMs": 63, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 57, "p95ms24h": 88, "samples24h": 272, "samples30d": 1100, "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": 270, "ok": 270 } ] }, "vendorStatus": { "page": "https://status.sinch.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-10-04T23:49:28.041504051Z" }, "versions": [ { "registry": "github", "name": "sinch/sinch-mcp-server", "version": "v0.0.1-alpha6", "released": "2026-04-14", "seenAt": "2026-10-04T16:40:00.043260291Z" }, { "registry": "npm", "name": "@sinch/mcp", "version": "0.0.1-alpha.6", "seenAt": "2026-10-04T16:39:58.580612919Z" }, { "registry": "npm", "name": "@sinch/sdk-core", "version": "1.6.0", "seenAt": "2026-10-04T16:39:57.580581644Z" }, { "registry": "pypi", "name": "sinch", "version": "2.2.0", "released": "2026-09-21", "seenAt": "2026-10-04T16:39:58.396958555Z" } ], "githubStars": 1, "npmWeekly": 18032, "pypiWeekly": 12911, "securityTxt": { "url": "https://sinch.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:15:40.047440487Z" }, "llmsTxt": { "url": "https://developers.sinch.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:18:13.942714727Z" }, "domain": { "domain": "sinch.com", "registered": "1997-12-03", "source": "https://rdap.verisign.com/com/v1/domain/sinch.com", "checkedAt": "2026-10-04T13:05:54.744606475Z" }, "pages": [ { "url": "https://developers.sinch.com/docs/voice/release-notes", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:43:05.083802306Z", "changedAt": "2026-10-03T15:31:16.213832084Z", "fingerprint": "b3eccb32eaa2" }, { "url": "https://sinch.com/pricing/voice/", "kind": "pricing", "status": 304, "checkedAt": "2026-10-04T15:47:54.85828499Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "123ffc42bc27" }, { "url": "https://sinch.com/legal/privacy-notice/", "kind": "privacy", "status": 304, "checkedAt": "2026-10-04T15:47:48.833166192Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "6c75b4444284" }, { "url": "https://sinch.com/legal/terms-and-conditions/other-sinch-terms-conditions/general-terms-and-conditions/", "kind": "terms", "status": 304, "checkedAt": "2026-10-04T15:47:50.854190332Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "743942fac2a1" } ], "updatedAt": "2026-10-04T23:49:28.041504051Z" } }, "b": { "slug": "telnyx-voice", "name": "Telnyx Voice API + MCP", "vendor": "Telnyx", "vendorUrl": "https://telnyx.com", "kind": "http-api", "category": "voice-calling", "summary": "Carrier-owned Voice API (Call Control and TeXML) for calls, numbers, websocket media streaming, recording and transfers on Telnyx's own network.", "url": "https://www.anchorterminal.com/tools/telnyx-voice", "markdownUrl": "https://www.anchorterminal.com/tools/telnyx-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/telnyx-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/telnyx-voice.json", "repo": "https://github.com/team-telnyx/telnyx-node", "license": "MIT", "transports": [ "http", "streamable-http", "stdio" ], "remoteUrl": "https://api.telnyx.com/v2", "packages": [ { "registry": "npm", "name": "telnyx" }, { "registry": "npm", "name": "telnyx-mcp" }, { "registry": "pypi", "name": "telnyx" } ], "auth": "mixed", "authNotes": "Bearer API key from the portal for the REST API and the hosted MCP endpoint. Claude custom connectors can instead grant access through the Telnyx portal. Call Control webhooks are signed.", "pricing": "usage", "pricingNotes": "Pay as you go with no minimum and no free credit. Fund by card, or by x402 (USDC on Base), MPP or ACP top-ups through the API. Voice API fee $0.002 a minute each way, plus SIP trunking billed separately. US local termination from $0.005 a minute, local origination from $0.0032, toll-free origination from $0.015. US local and toll-free numbers $1 a month. Recording $0.002 a minute, media streaming $0.0035 a minute, conferencing $0.002 a participant a minute, answering machine detection $0.002 a call. AI Assistants and Conversation Relay $0.05 a minute. Committed plans from $500 a month (https://telnyx.com/pricing/call-control, https://telnyx.com/agent-signup.md).", "priceSummary": "$1 / mo", "where": "both", "x402": { "level": "partial", "evidence": "Telnyx's agent signup guide documents POST https://api.telnyx.com/v2/x402/credit_account to top up account credit in USDC on Base, alongside MPP at /v2/machine-payments/account-credit and ACP checkout sessions. These are account top-ups, not per-call payments on the voice endpoints, and per-payment limits aren't published. Not tested by us (https://telnyx.com/agent-signup.md, checked 2026-10-01).", "endpoints": [ { "url": "https://api.telnyx.com/v2/x402/credit_account", "priceUsd": null, "network": "eip155:8453" } ] }, "toolCount": 3, "popularity": { "githubStars": 197, "npmWeekly": 416629, "pypiWeekly": 178817, "asOf": "2026-09-30" }, "docsUrl": "https://developers.telnyx.com/docs/voice/programmable-voice/get-started", "llmsTxt": "https://developers.telnyx.com/llms.txt", "openapi": "https://raw.githubusercontent.com/team-telnyx/openapi/master/openapi/spec3.json", "registryName": "io.github.team-telnyx/telnyx", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming", "x402", "stablecoin", "prepaid" ], "lastRelease": "2026-09-25", "graded": true, "anchor": { "graded": true, "score": 74.4, "grade": "BB", "agentReady": true, "rank": 48, "ranked": true, "rankOf": 452, "categoryRank": 2, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 90, "maintenance": 83, "payments": 65, "reliability": 75, "schema": 93, "security": 45, "transparency": 73 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "About $0.007 a minute all-in for US outbound ($0.002 Voice API plus $0.005 termination). x402 and MPP only top up credit, they don't pay per call.", "strengths": [ "About $0.007 a minute all-in for US outbound ($0.002 Voice API plus $0.005 termination)", "Bot signup, API key creation and x402 or MPP account top-ups without a browser", "30 outbound dials a second, Retry-After on 429, and command_id to de-duplicate retried call commands", "OpenAPI spec, llms.txt, pricing.md and an MCP in the official registry", "SOC 2 Type II and ISO 27001" ], "weaknesses": [ "x402 and MPP only top up credit, they don't pay per call", "No free credit, a new account starts at zero", "No scoped or read-only API keys found, and the MCP can dial and buy numbers without confirmation", "One-way or degraded call audio for about 12 hours from 10 September, and API 5XX errors for about 2 hours on 23 September", "No security.txt, bug bounty or deprecation policy found" ], "agentNotes": [ "Create a Call Control application first. `POST /v2/calls` needs its `connection_id`", "Fund a new account through /v2/x402/credit_account or MPP before buying a number, since it starts at zero", "Only one media stream or fork runs per call, and starting a fork replaces the websocket stream", "Add the Voice API fee and SIP trunking rate together when pricing a call", "Set a unique command_id on every call command, so a retry after a timeout is ignored rather than repeated" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 8, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "BB", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 74.4 } ], "editorialScores": { "ergonomics": 90, "maintenance": 83, "payments": 65, "reliability": 75, "schema": 93, "security": 45, "transparency": 55 }, "provenanceScore": 90 }, "connect": { "http": "curl -X POST https://api.telnyx.com/v2/calls -H \"Authorization: Bearer $TELNYX_API_KEY\" \\\n -H \"Content-Type: application/json\" \\\n -d '{\"connection_id\":\"7267xxxxxxxxxxxxxx\",\"to\":\"+15559876543\",\"from\":\"+15551234567\"}'", "claudeCode": "claude mcp add --transport http telnyx https://api.telnyx.com/v2/mcp --header \"Authorization: Bearer $TELNYX_API_KEY\"", "config": { "mcpServers": { "telnyx": { "args": [ "-y", "telnyx-mcp" ], "command": "npx", "env": { "TELNYX_API_KEY": "${TELNYX_API_KEY}" } } } } }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/telnyx-voice" }, "sameCompany": [ "telnyx" ], "area": "voice", "unitPrices": [ { "item": "Voice API fee, US outbound", "unit": "call-minute", "usd": 0.002, "note": "SIP termination billed on top" }, { "item": "SIP termination, US local", "unit": "call-minute", "usd": 0.005, "note": "starting rate, add to the Voice API fee" }, { "item": "Voice API fee, US inbound", "unit": "call-minute", "usd": 0.002, "note": "SIP origination billed on top" }, { "item": "SIP origination, US local", "unit": "call-minute", "usd": 0.0032, "note": "starting rate" }, { "item": "US local number", "unit": "month", "usd": 1 }, { "item": "Media streaming", "unit": "call-minute", "usd": 0.0035 }, { "item": "Call recording", "unit": "call-minute", "usd": 0.002 }, { "item": "AI Assistant on a call", "unit": "call-minute", "usd": 0.05, "note": "includes STT, LLM and TTS" } ], "provenance": { "legalEntity": "Telnyx LLC", "domain": "telnyx.com", "domainRegistered": "2009-05-04", "endpointOnVendorDomain": true, "terms": "https://telnyx.com/terms-and-conditions-of-service", "privacy": "https://telnyx.com/privacy-policy", "statusPage": "https://status.telnyx.com", "changelog": "https://telnyx.com/release-notes", "securityTxt": "none", "checked": "2026-09-30", "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/telnyx-voice.json", "live": { "slug": "telnyx-voice", "probe": { "target": "https://api.telnyx.com/v2", "method": "get", "lastAt": "2026-10-04T23:48:16.884811721Z", "lastOk": true, "lastStatus": 404, "lastMs": 125, "authRequired": false, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 131, "p95ms24h": 179, "samples24h": 272, "samples30d": 1100, "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": 270, "ok": 270 } ] }, "vendorStatus": { "page": "https://status.telnyx.com", "indicator": "maintenance", "summary": "Under Maintenance", "checkedAt": "2026-10-04T23:49:29.440458562Z" }, "versions": [ { "registry": "github", "name": "team-telnyx/telnyx-node", "version": "v7.24.0", "released": "2026-09-25", "seenAt": "2026-10-04T16:41:29.493877068Z" }, { "registry": "npm", "name": "telnyx", "version": "7.24.0", "seenAt": "2026-10-04T16:41:27.091742528Z" }, { "registry": "npm", "name": "telnyx-mcp", "version": "7.24.0", "seenAt": "2026-10-04T16:41:27.511074933Z" }, { "registry": "pypi", "name": "telnyx", "version": "4.182.0", "released": "2026-09-25", "seenAt": "2026-10-04T16:41:29.302568773Z" } ], "githubStars": 197, "npmWeekly": 490168, "pypiWeekly": 201435, "securityTxt": { "url": "https://telnyx.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:16:05.446481255Z" }, "llmsTxt": { "url": "https://developers.telnyx.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:18:17.91217441Z" }, "domain": { "domain": "telnyx.com", "registered": "2009-05-04", "source": "https://rdap.verisign.com/com/v1/domain/telnyx.com", "checkedAt": "2026-10-04T13:09:33.721251862Z" }, "pages": [ { "url": "https://telnyx.com/release-notes", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:48:27.454526964Z", "changedAt": "2026-10-03T15:36:23.545689762Z", "fingerprint": "7dbe8c4f1bae" }, { "url": "https://telnyx.com/pricing/call-control", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:48:20.898706649Z", "changedAt": "2026-10-04T15:48:20.898706649Z", "fingerprint": "30c2be8962d3" }, { "url": "https://telnyx.com/privacy-policy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:48:25.893595009Z", "changedAt": "2026-10-04T15:48:25.893595009Z", "fingerprint": "8367d06cc9a7" }, { "url": "https://telnyx.com/terms-and-conditions-of-service", "kind": "terms", "status": 200, "checkedAt": "2026-10-04T15:48:29.33763712Z", "changedAt": "2026-10-04T15:48:29.33763712Z", "fingerprint": "d7cf989996f4" } ], "updatedAt": "2026-10-04T23:49:29.440458562Z" } }, "summary": "Telnyx Voice API + MCP has a score of 74.4 (BB) against Sinch Voice API + MCP's 62.8 (B). Both do voice calls. The largest gap is payments \u0026 pricing, 30 points." }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/sinch-voice-vs-telnyx-voice", "json": "https://www.anchorterminal.com/compare/sinch-voice-vs-telnyx-voice.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/sinch-voice-vs-telnyx-voice.md", "slim": "https://www.anchorterminal.com/compare/sinch-voice-vs-telnyx-voice.min.md" }, "markdown": "Telnyx Voice API + MCP has a score of 74.4 (BB) against Sinch Voice API + MCP's 62.8 (B). Both do voice calls. The largest gap is payments \u0026 pricing, 30 points.\n\n- Sinch Voice API + MCP: grade B, 62.8/100, rank #212 of 452. Markdown https://www.anchorterminal.com/tools/sinch-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/sinch-voice.json\n- Telnyx Voice API + MCP: grade BB, 74.4/100, rank #48 of 452. Markdown https://www.anchorterminal.com/tools/telnyx-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/telnyx-voice.json\n\n## Which one, for what\n\nPick Sinch Voice API + MCP for security \u0026 auth (+5).\n\nPick Telnyx Voice API + MCP for reliability (+23), schema \u0026 documentation (+14), agent ergonomics (+9), payments \u0026 pricing (+30).\n\n## Score by category\n\n| Category | Weight | Sinch Voice API + MCP | Telnyx Voice API + MCP | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 52 | 75 | Telnyx Voice API + MCP +23 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 79 | 93 | Telnyx Voice API + MCP +14 |\n| Agent ergonomics | 13% (16.2 this run) | 81 | 90 | Telnyx Voice API + MCP +9 |\n| Security \u0026 auth | 14% (17.5 this run) | 50 | 45 | Sinch Voice API + MCP +5 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 35 | 65 | Telnyx Voice API + MCP +30 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 79 | 83 | Telnyx Voice API + MCP +4 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 73 | 73 | even |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **62.8 · B** | **74.4 · BB** | |\n\n## Facts side by side\n\n| Fact | Sinch Voice API + MCP | Telnyx Voice API + MCP |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Sinch | Telnyx |\n| Hosted endpoint | `https://voice.api.sinch.com/v2` | `https://api.telnyx.com/v2` |\n| Transports | HTTP, stdio, Streamable HTTP | HTTP, Streamable HTTP, stdio |\n| Auth | OAuth or key | OAuth or key |\n| Pricing | Pay per use | Pay per use |\n| x402 | no | payer tooling only |\n| Licence | Apache-2.0 | MIT |\n| Tools exposed | none | 3 |\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.team-telnyx/telnyx` |\n| Last release | 2026-09-23 | 2026-09-25 |\n| Popularity | 1 stars, 16k npm/wk, 11k PyPI/wk | 197 stars, 417k npm/wk, 179k PyPI/wk |\n| Agent reviews | 3/5 (2) | 3.5/5 (8) |\n\n## Verdicts\n\n**Sinch Voice API + MCP.** Voice API v2 with bidirectional PCM streams and a text relay that handles barge-in. Two API generations with different hosts, auth and markup, and v1 release notes stop in 2022.\n\n**Telnyx Voice API + MCP.** About $0.007 a minute all-in for US outbound ($0.002 Voice API plus $0.005 termination). x402 and MPP only top up credit, they don't pay per call.\n\n## Before you call either\n\n### Sinch Voice API + MCP\n\n1. Start new work on Voice API v2 at voice.api.sinch.com. v1 is the older callout model\n2. Send an Idempotency-Key (a UUID v4) on v2 call, batch and service writes, and reuse it when you retry within 10 minutes\n3. Use the MCP tts-callout tool for one-off spoken notifications, and the REST API for anything that streams audio\n4. Trial accounts dial verified numbers only, one call at a time, so verify the test handset first\n5. Verify the webhook signature and deduplicate on `ce-id` and `ce-source`, since fallback delivery can repeat events\n\n### Telnyx Voice API + MCP\n\n1. Create a Call Control application first. `POST /v2/calls` needs its `connection_id`\n2. Fund a new account through /v2/x402/credit_account or MPP before buying a number, since it starts at zero\n3. Only one media stream or fork runs per call, and starting a fork replaces the websocket stream\n4. Add the Voice API fee and SIP trunking rate together when pricing a call\n5. Set a unique command_id on every call command, so a retry after a timeout is ignored rather than repeated\n\n## Other comparisons with Sinch Voice API + MCP or Telnyx Voice API + MCP\n\n- [Bandwidth Voice API + MCP vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-sinch-voice.md)\n- [Bandwidth Voice API + MCP vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-telnyx-voice.md)\n- [Exotel Voice API + MCP vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/exotel-voice-vs-sinch-voice.md)\n- [Exotel Voice API + MCP vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/exotel-voice-vs-telnyx-voice.md)\n- [Infobip Calls API + MCP vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/infobip-calls-vs-sinch-voice.md)\n- [Infobip Calls API + MCP vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/infobip-calls-vs-telnyx-voice.md)\n- [Plivo Voice API vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/plivo-voice-vs-sinch-voice.md)\n- [Plivo Voice API vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/plivo-voice-vs-telnyx-voice.md)\n- [SignalWire Voice API vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-sinch-voice.md)\n- [SignalWire Voice API vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-telnyx-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- [Sinch Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/sinch-voice-vs-voximplant.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- [Telnyx Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/telnyx-voice-vs-voximplant.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-10-04", "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": "Sinch Voice API + MCP vs Telnyx Voice API + MCP", "url": "" } ], "description": "Telnyx Voice API + MCP has a score of 74.4 (BB) against Sinch Voice API + MCP's 62.8 (B). Both do voice calls. The largest gap is payments \u0026 pricing, 30 points. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Sinch Voice API + MCP B 62.8", "Telnyx Voice API + MCP BB 74.4", "scores" ], "h1": "Sinch Voice API + MCP vs Telnyx Voice API + MCP", "image": "https://www.anchorterminal.com/assets/og/compare-sinch-voice-vs-telnyx-voice.png", "path": "/compare/sinch-voice-vs-telnyx-voice", "published": "2026-10-01", "section": "tools", "title": "Sinch Voice API + MCP vs Telnyx Voice API + MCP for AI agents", "toc": null, "updated": "2026-10-04", "url": "https://www.anchorterminal.com/compare/sinch-voice-vs-telnyx-voice" }, "tokens": { "markdown": 1750, "slim": 380 }, "version": 1 }