{ "data": { "a": { "slug": "inworld-stt", "name": "Inworld STT", "vendor": "Inworld AI", "vendorUrl": "https://inworld.ai", "kind": "model", "category": "speech-to-text", "summary": "Inworld's speech-to-text API runs its `inworld/inworld-stt-1` model in 30 languages over synchronous HTTP, bidirectional WebSocket streaming and asynchronous jobs, returning Voice Profile signals (age, emotion, pitch, accent) and turn detection alongside the transcript.", "url": "https://www.anchorterminal.com/tools/inworld-stt", "markdownUrl": "https://www.anchorterminal.com/tools/inworld-stt.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/inworld-stt.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/inworld-stt.json", "dns": "inworld-stt.grade.anchorterminal.com", "transports": [ "http", "websocket" ], "packages": [ { "registry": "npm", "name": "@inworld/cli" } ], "auth": "api-key", "authNotes": "Every call sends `Authorization: Basic` with the Base64 `key_id:secret` credential from the Portal or the CLI. Keys belong to a workspace and are deleted to revoke. Browsers pass a one-time token in the `bearer_` WebSocket subprotocol rather than the URL.", "pricing": "usage", "pricingNotes": "$0.15 an hour of audio on the free On-Demand plan and $0.10 on the paid plans ($25 to $1,500 a month), billed per second. On-Demand includes up to 400 minutes free. Diarisation and Voice Profile are separate per-second add-ons. Asynchronous jobs need a payment method.", "priceSummary": "Pay per use", "where": "local", "x402": { "level": "no", "evidence": "No x402, MPP or L402 in the docs, llms.txt or pricing page (checked 2026-11-06). Plans and credits are bought in the Portal.", "endpoints": [] }, "toolCount": 0, "popularity": { "githubStars": null, "npmWeekly": null, "pypiWeekly": null, "asOf": "2026-11-06" }, "docsUrl": "https://docs.inworld.ai/stt/overview", "llmsTxt": "https://docs.inworld.ai/llms.txt", "capabilities": [ "speech.stt", "speech.streaming", "speech.batch", "speech.diarisation", "speech.languages" ], "tags": [ "hosted", "usage", "free-tier", "no-card", "closed-source", "llms-txt", "streaming", "batch", "mcp", "enterprise" ], "lastRelease": "2026-10-29", "graded": true, "anchor": { "graded": true, "score": 54.7, "grade": "C", "agentReady": false, "rank": 895, "ranked": true, "rankOf": 1486, "categoryRank": 16, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 56, "maintenance": 41, "payments": 40, "reliability": 60, "schema": 54, "security": 63, "transparency": 60 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-06" }, "negative": 0, "verdict": "Inworld STT costs $0.10 to $0.15 an hour with 400 free minutes, and covers files, live streams and async jobs in 30 languages with Voice Profile signals. There is no machine-readable spec, no public STT changelog and no readable status history, and diarisation is still experimental.", "bestFor": "Low-cost live transcription for voice agents, with speaker traits.", "strengths": [ "$0.15 an hour on the free plan and $0.10 on paid plans, billed per second, with 400 free minutes", "Sync, WebSocket streaming and async jobs on one model, with turn detection and Voice Profile signals", "Browser tokens travel in a WebSocket subprotocol, not the URL", "Zero data retention keeps audio and transcripts in memory, and the docs include it from the Developer plan", "llms.txt, Markdown twins and a docs MCP server" ], "weaknesses": [ "No OpenAPI or other machine-readable contract", "The STT release notes path asks for a login, so changes to the model aren't publicly dated", "Status history couldn't be read, and an SLA exists only for Enterprise", "Speaker diarisation is experimental and async jobs run on a `v1alpha` operations route", "Docs and the STT product page disagree on which plans include zero data retention" ], "agentNotes": [ "Send the Base64 credential as-is in `Authorization: Basic`; don't encode it again", "Wrap the first WebSocket message in `transcribeConfig`, because a malformed first frame closes the socket with 1005 and no error", "Use `POST /stt/v1/transcribe:async` for files over about 16 MB and collect the transcript within 7 days", "Retry 429 or gRPC code 8 with exponential backoff and jitter, and stay within the plan's streaming concurrency", "Stop sending audio when nobody speaks, since streams are billed for every second sent" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 0, "avgRating": 0, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "C", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 54.7 } ], "editorialScores": { "ergonomics": 56, "maintenance": 41, "payments": 40, "reliability": 60, "schema": 54, "security": 63, "transparency": 45 }, "provenanceScore": 75, "checked": { "categories": { "ergonomics": "2026-11-06", "maintenance": "2026-11-06", "payments": "2026-11-06", "reliability": "2026-11-06", "schema": "2026-11-06", "security": "2026-11-06", "transparency": "2026-11-06" }, "last": "2026-11-06", "oldest": "2026-11-06", "stale": false, "staleAfterDays": 90 } }, "connect": { "install": "npm install -g @inworld/cli", "claudeCode": "claude mcp add inworld -- inworld mcp" }, "letme": { "capability": "https://letme.dev/speech.stt", "tool": "https://letme.dev/inworld-stt" }, "sameCompany": [ "inworld-tts", "inworld-realtime", "inworld-voice-cloning" ], "area": "voice", "unitPrices": [ { "item": "STT-1, On-Demand", "unit": "audio-minute", "usd": 0.0025, "note": "$0.15 an hour" }, { "item": "STT-1, paid plans", "unit": "audio-minute", "usd": 0.00167, "note": "$0.10 an hour on Creator to Growth" } ], "provenance": { "legalEntity": "Theai, Inc. dba Inworld AI", "domain": "inworld.ai", "domainRegistered": "", "endpointOnVendorDomain": true, "terms": "https://inworld.ai/terms", "privacy": "https://inworld.ai/privacy", "statusPage": "https://status.inworld.ai", "changelog": "https://docs.inworld.ai/release-notes/realtime", "securityTxt": "none", "checked": "2026-11-06", "notes": [ "The Terms of Service (effective 11 June 2025) are an agreement with Theai, Inc. dba Inworld AI under California law, with courts in Santa Clara. The Privacy Notice (last updated 18 January 2026) names Theai, Inc.", "inworld.ai/.well-known/security.txt returns 404. The security page links a vulnerability report form.", "status.inworld.ai runs the open-source issue-status app, which draws incidents from GitHub issues in inworld-ai/inworld-issue-status. Its history wasn't read, because GitHub's robots.txt couldn't be read from our environment.", "inworld.ai's robots.txt allows Claude agents on the paths read and sets `Content-Signal: ai-train=no, search=yes, ai-input=no`. docs.inworld.ai has no such signal.", "The domain's registration date wasn't established, because the RDAP lookup failed.", "firstReleased is left empty. No dated STT launch was found, and the STT release notes path asks for a Portal login." ], "score": 75 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/inworld-stt.json", "live": { "slug": "inworld-stt", "versions": [ { "registry": "npm", "name": "@inworld/cli", "version": "1.5.0", "seenAt": "2026-11-06T23:35:05.474861108Z" } ], "npmWeekly": 290, "securityTxt": { "url": "https://inworld.ai/.well-known/security.txt", "state": "none", "checkedAt": "2026-11-07T16:01:11.794771951Z" }, "llmsTxt": { "url": "https://docs.inworld.ai/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-11-07T15:32:47.741512787Z" }, "updatedAt": "2026-11-07T16:01:11.794771951Z" } }, "answer": "Speechmatics Speech-to-Text scores 67.8 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 6 of 7 scored categories.", "b": { "slug": "speechmatics-stt", "name": "Speechmatics Speech-to-Text", "vendor": "Speechmatics", "vendorUrl": "https://www.speechmatics.com", "kind": "model", "category": "speech-to-text", "summary": "Speechmatics' APIs for batch and real-time transcription, including speaker-attributed turns for voice agents.", "url": "https://www.anchorterminal.com/tools/speechmatics-stt", "markdownUrl": "https://www.anchorterminal.com/tools/speechmatics-stt.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/speechmatics-stt.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/speechmatics-stt.json", "dns": "speechmatics-stt.grade.anchorterminal.com", "repo": "https://github.com/speechmatics/speechmatics-python-sdk", "license": "MIT (SDKs)", "transports": [ "http" ], "remoteUrl": "https://eu1.asr.api.speechmatics.com/v2", "packages": [ { "registry": "npm", "name": "@speechmatics/batch-client" }, { "registry": "npm", "name": "@speechmatics/real-time-client" }, { "registry": "pypi", "name": "speechmatics-batch" }, { "registry": "pypi", "name": "speechmatics-rt" } ], "auth": "api-key", "authNotes": "API key as a Bearer token. Short-lived JWTs for browser and realtime clients, passed as `?jwt=` on the WebSocket URL. A separate management token covers project and key administration.", "pricing": "usage", "pricingNotes": "$100 free credit with no card, then credits at $1 each before discounts, billed per hour of audio. Pre-recorded Melia 1 $0.12, Oak 1 $0.15, Standard $0.23, Enhanced $0.38. Realtime Melia 1 $0.20, Oak 1 $0.23, Standard $0.23, Enhanced $0.40, Linden 1 (Agent STT) $0.15 (was $0.20). Translation adds $0.49 an hour. Credit packs and subscriptions give up to 25 per cent off, and opting in to model training 33 per cent off. Sign-up and pack credits last 12 months (https://www.speechmatics.com/pricing).", "priceSummary": "Pay per use", "where": "hosted", "x402": { "level": "no", "evidence": "No x402 or machine payment in the docs or pricing. Card or prepaid credits only (checked 2026-09-30).", "endpoints": [] }, "toolCount": null, "popularity": { "githubStars": 20, "npmWeekly": 58050, "pypiWeekly": 48085, "asOf": "2026-09-30" }, "docsUrl": "https://docs.speechmatics.com", "llmsTxt": "https://docs.speechmatics.com/llms.txt", "openapi": "https://docs.speechmatics.com/batch.yaml", "capabilities": [ "speech.stt", "speech.streaming", "speech.batch", "speech.diarisation", "speech.languages", "speech.translation" ], "tags": [ "hosted", "no-card", "closed-source", "python", "typescript", "llms-txt", "streaming", "batch", "webhooks", "async-jobs", "enterprise", "self-hosted" ], "lastRelease": "2026-10-26", "graded": true, "anchor": { "graded": true, "score": 67.8, "grade": "B", "agentReady": false, "rank": 305, "ranked": true, "rankOf": 1486, "categoryRank": 9, "methodology": "0.7", "run": "2026-10-01", "scores": { "ergonomics": 80, "maintenance": 70, "payments": 40, "reliability": 70, "schema": 90, "security": 65, "transparency": 76 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-11-01" }, "negative": -3, "negativeNotes": [ "7 August 2026, -3. Published behaviour changed for existing clients, announced the day it took effect. The 2026.08.07 Batch SaaS changelog entry says the default behaviour of GET /jobs/{jobid} and GET /jobs/{jobid}/transcript \"is changing\" so requests wait up to 2 seconds before returning unless the caller sends `wait=0`, and the docs were changed the same day. The rise to 5 seconds was likewise announced in the 2026.09.23 entry on the day it applied (the August docs said only that the default \"will increase\"), and folds into the same term (https://speechmatics.featurebase.app/en/changelog/20260807-batch-saas)" ], "verdict": "Training is opt-in and real-time audio is not stored. Enhanced transcription costs $0.38 an hour for files and $0.40 for live audio.", "bestFor": "Regulated or privacy-sensitive audio, multilingual batch with Melia 1, and voice agents that want speaker-attributed turns.", "strengths": [ "Training is opt-in only, and realtime audio isn't stored", "ISO/IEC 27001:2022 and SOC 2 Type II", "A Swagger 2.0 file for the Batch API, linked from the API reference", "Transcripts fetched as plain text, JSON or SRT", "$100 credit with no card" ], "weaknesses": [ "Enhanced costs $0.38 to $0.40 an hour, above most rivals", "Batch options travel as a JSON string inside a multipart form field", "429s carry a reason but no Retry-After or backoff guidance", "Realtime temporary keys travel in the WebSocket URL", "Free plan allows 2 realtime sessions" ], "agentNotes": [ "Set `\"model\": \"enhanced\"` explicitly. The default is `standard`", "Use notifications instead of polling. Polling waits 5 seconds by default since the 23 September 2026 change, and `wait=0` turns that off", "Fetch batch transcripts within 7 days. After that the API returns 404 `expired`", "Pass a `fetch_data` URL for files over 1 GB", "Use `/v2/agent` with `linden-1` for live agents instead of the plain realtime path", "Read the Batch API's Swagger file at https://docs.speechmatics.com/batch.yaml before building the multipart `config` field" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.7", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 67.8 } ], "editorialScores": { "ergonomics": 80, "maintenance": 70, "payments": 40, "reliability": 70, "schema": 90, "security": 65, "transparency": 65 }, "provenanceScore": 87, "checked": { "categories": { "ergonomics": "2026-11-01", "maintenance": "2026-11-01", "payments": "2026-11-01", "reliability": "2026-11-01", "schema": "2026-11-01", "security": "2026-11-01", "transparency": "2026-11-01" }, "last": "2026-11-01", "lastMoved": "2026-11-01", "oldest": "2026-11-01", "stale": false, "staleAfterDays": 90 } }, "connect": { "http": "curl -X POST https://eu1.asr.api.speechmatics.com/v2/jobs/ -H \"Authorization: Bearer $SPEECHMATICS_API_KEY\" \\\n -F data_file=@call.wav \\\n -F config='{\"type\":\"transcription\",\"transcription_config\":{\"language\":\"en\",\"model\":\"enhanced\",\"diarization\":\"speaker\"}}'" }, "letme": { "capability": "https://letme.dev/speech.stt", "tool": "https://letme.dev/speechmatics-stt" }, "area": "voice", "unitPrices": [ { "item": "Batch Melia 1", "unit": "audio-minute", "usd": 0.002, "note": "published as $0.12 an hour" }, { "item": "Batch Oak 1", "unit": "audio-minute", "usd": 0.0025, "note": "published as $0.15 an hour" }, { "item": "Batch Standard", "unit": "audio-minute", "usd": 0.0038, "note": "published as $0.23 an hour" }, { "item": "Batch Enhanced", "unit": "audio-minute", "usd": 0.0063, "note": "published as $0.38 an hour" }, { "item": "Realtime Melia 1", "unit": "audio-minute", "usd": 0.0033, "note": "published as $0.20 an hour" }, { "item": "Realtime Oak 1", "unit": "audio-minute", "usd": 0.0038, "note": "published as $0.23 an hour" }, { "item": "Realtime Standard", "unit": "audio-minute", "usd": 0.0038, "note": "published as $0.23 an hour" }, { "item": "Realtime Enhanced", "unit": "audio-minute", "usd": 0.0067, "note": "published as $0.40 an hour" }, { "item": "Linden 1 Agent STT", "unit": "audio-minute", "usd": 0.0025, "note": "published as $0.15 an hour, reduced from $0.20" }, { "item": "Translation add-on", "unit": "audio-minute", "usd": 0.0082, "note": "published as $0.49 an hour" } ], "provenance": { "legalEntity": "Cantab Research Ltd", "domain": "speechmatics.com", "domainRegistered": "2006-05-10", "endpointOnVendorDomain": true, "terms": "https://www.speechmatics.com/legal/terms-of-service", "privacy": "https://www.speechmatics.com/legal/privacy-policy", "statusPage": "https://status.speechmatics.com", "changelog": "https://speechmatics.featurebase.app/en/changelog", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "Trades as Speechmatics, company number 05697423 in England and Wales. US customers contract with Speechmatics (USA) Inc., a Delaware company" ], "score": 87 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/speechmatics-stt.json", "live": { "slug": "speechmatics-stt", "probe": { "target": "https://eu1.asr.api.speechmatics.com/v2", "method": "get", "lastAt": "2026-11-07T18:20:56.282256416Z", "lastOk": true, "lastStatus": 200, "lastMs": 192, "authRequired": false, "uptime24h": 100, "uptime30d": 99.99, "p50ms24h": 84, "p95ms24h": 319, "samples24h": 239, "samples30d": 7910, "days": [ { "date": "2026-10-07", "probes": 272, "ok": 272 }, { "date": "2026-10-08", "probes": 268, "ok": 268 }, { "date": "2026-10-09", "probes": 250, "ok": 250 }, { "date": "2026-10-10", "probes": 247, "ok": 247 }, { "date": "2026-10-11", "probes": 247, "ok": 247 }, { "date": "2026-10-12", "probes": 247, "ok": 247 }, { "date": "2026-10-13", "probes": 248, "ok": 248 }, { "date": "2026-10-14", "probes": 249, "ok": 249 }, { "date": "2026-10-15", "probes": 253, "ok": 253 }, { "date": "2026-10-16", "probes": 252, "ok": 252 }, { "date": "2026-10-17", "probes": 253, "ok": 253 }, { "date": "2026-10-18", "probes": 256, "ok": 256 }, { "date": "2026-10-19", "probes": 255, "ok": 255 }, { "date": "2026-10-20", "probes": 252, "ok": 252 }, { "date": "2026-10-21", "probes": 253, "ok": 253 }, { "date": "2026-10-22", "probes": 253, "ok": 253 }, { "date": "2026-10-23", "probes": 248, "ok": 248 }, { "date": "2026-10-24", "probes": 251, "ok": 251 }, { "date": "2026-10-25", "probes": 250, "ok": 250 }, { "date": "2026-10-26", "probes": 252, "ok": 252 }, { "date": "2026-10-27", "probes": 249, "ok": 249 }, { "date": "2026-10-28", "probes": 250, "ok": 250 }, { "date": "2026-10-29", "probes": 249, "ok": 249 }, { "date": "2026-10-30", "probes": 249, "ok": 249 }, { "date": "2026-10-31", "probes": 251, "ok": 251 }, { "date": "2026-11-01", "probes": 249, "ok": 249 }, { "date": "2026-11-02", "probes": 250, "ok": 250 }, { "date": "2026-11-03", "probes": 248, "ok": 247 }, { "date": "2026-11-04", "probes": 246, "ok": 246 }, { "date": "2026-11-05", "probes": 185, "ok": 185 }, { "date": "2026-11-06", "probes": 241, "ok": 241 }, { "date": "2026-11-07", "probes": 187, "ok": 187 } ] }, "vendorStatus": { "page": "https://status.speechmatics.com", "indicator": "none", "summary": "All Systems Operational", "checkedAt": "2026-11-07T18:22:02.437503825Z" }, "versions": [ { "registry": "github", "name": "speechmatics/speechmatics-python-sdk", "version": "tts/v0.2.0", "released": "2026-11-06", "seenAt": "2026-11-07T00:07:36.269591228Z" }, { "registry": "npm", "name": "@speechmatics/batch-client", "version": "5.4.2", "seenAt": "2026-11-07T00:07:31.891316877Z" }, { "registry": "npm", "name": "@speechmatics/real-time-client", "version": "8.6.2", "seenAt": "2026-11-07T00:07:32.6887692Z" }, { "registry": "pypi", "name": "speechmatics-batch", "version": "1.2.0", "released": "2026-11-06", "seenAt": "2026-11-07T00:07:34.261012083Z" }, { "registry": "pypi", "name": "speechmatics-rt", "version": "1.3.0", "released": "2026-11-06", "seenAt": "2026-11-07T00:07:34.401834825Z" } ], "githubStars": 20, "npmWeekly": 38070, "pypiWeekly": 18992, "securityTxt": { "url": "https://speechmatics.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-11-07T16:02:02.489220382Z" }, "llmsTxt": { "url": "https://docs.speechmatics.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-11-07T15:34:00.505658242Z" }, "domain": { "domain": "speechmatics.com", "registered": "2006-05-10", "source": "https://rdap.verisign.com/com/v1/domain/speechmatics.com", "checkedAt": "2026-11-01T14:25:12.815432254Z" }, "pages": [ { "url": "https://speechmatics.featurebase.app/en/changelog", "kind": "changelog", "status": 200, "checkedAt": "2026-11-07T14:20:30.550182583Z", "changedAt": "2026-11-05T13:04:51.469987554Z", "fingerprint": "48c0286c371c" }, { "url": "https://www.speechmatics.com/pricing", "kind": "pricing", "status": 304, "checkedAt": "2026-11-07T14:35:02.408280219Z", "changedAt": "2026-10-31T06:32:46.178807389Z", "fingerprint": "418585bd0fd0" }, { "url": "https://www.speechmatics.com/legal/privacy-policy", "kind": "privacy", "status": 304, "checkedAt": "2026-11-07T14:34:58.219976764Z", "changedAt": "2026-11-05T13:18:23.646886306Z", "fingerprint": "a7da558c513a" }, { "url": "https://www.speechmatics.com/legal/terms-of-service", "kind": "terms", "status": 304, "checkedAt": "2026-11-07T14:35:00.643106701Z", "changedAt": "2026-10-02T15:28:24.437639084Z", "fingerprint": "33b19ec6fdcb" } ], "github": { "repo": "speechmatics/speechmatics-python-sdk", "checkedAt": "2026-11-02T09:27:04.130422133Z", "stars": 20, "archived": false, "issuesEnabled": true, "pushedAt": "2026-10-28T13:31:15Z", "openIssues": 7, "openPRs": 14, "issuesOpened90d": 3, "issuesClosed90d": 1, "prsMerged90d": 12, "ci": { "branch": "main", "runs": 50, "success": 50, "failure": 0, "other": 0, "latest": "success", "latestAt": "2026-10-26T09:58:58Z" }, "replies": { "sampled": 18, "unanswered": 6, "medianDays": 6 } }, "updatedAt": "2026-11-07T18:22:02.437503825Z" } }, "edges": [ { "by": 36, "category": "schema", "leads": "speechmatics-stt", "name": "Schema \u0026 documentation", "reasons": { "a": "No OpenAPI or other machine-readable file. The usual spec paths redirect, and the reference pages are Markdown (0). llms.txt, Markdown twins and a docs MCP server (10). Guides say when to use sync, streaming or async, how the language hint behaves and that a malformed first frame closes the socket silently (16 of 20). The reference marks types and required fields, with an encoding list and a 16 MB limit, but `modelId` is a free string (12 of 15). Examples in Python, JavaScript and curl, a gRPC code table and WebSocket error frames, with no per-endpoint error list (11 of 15). Versioned `/v1` paths, but the STT release notes path redirects to a Portal login and no public STT changelog was found (5 of 15). Total 54.", "b": "A Swagger 2.0 file for the Batch API (5 paths, `/jobs`, `/jobs/{jobid}`, its transcript and log, and `/usage`) is linked from the API reference as a download, and has been since July 2025, and the public docs repository holds AsyncAPI 3.0 files for Realtime and Agent STT (25). llms.txt and Markdown pages (10). Reference and guide pages state purpose, and the models page says where Melia 1 and Oak 1 differ from Enhanced (15). Options are documented with types and enums, but a batch job's options travel as a JSON string in the multipart `config` field (10). Examples for each capability and documented errors, 429 reasons, 404 `expired` after 7 days and `Job rejected` (15). Versioned `/v2` paths and a dated public changelog (15)." }, "scores": { "a": 54, "b": 90 } }, { "by": 29, "category": "maintenance", "leads": "speechmatics-stt", "name": "Maintenance \u0026 community", "reasons": { "a": "Read as a model. No public STT changelog. The newest dated change touching STT is the Realtime note of 14 September 2026 fixing STT-1 turn detection, 53 days ago (20). The CLI, which carries the STT command and MCP tool, shipped 1.4.0 to 1.5.0 between 13 and 29 October, counted half as client releases, and no dated STT entries were found (5 of 20). Discord and support@inworld.ai, with no evidence of answers read (6 of 15). No official STT SDK; the CLI is current (5 of 15). CLI on npm under MIT, current, CI not read (5 of 10). Total 41.", "b": "Model reading of the checklist, deprecation notice and support in place of release counts and issue replies. Changelog entries on 29 October 2026 for Batch SaaS and Agent STT, and speechmatics-rt 1.2.2 tagged on 26 October (30). Far more than three dated entries since 3 August, nine in October on the changelog's first page alone (10 of 10). No deprecation policy, and `operating_point`, the `region` field and the Voice SDK are marked deprecated with no removal date (0 of 10). A public changelog, a support portal with chat and email, and a community channel (10 of 15). SDK issues and reply times couldn't be read (0 of 10). Python packages speechmatics-batch 1.1.0 and speechmatics-rt 1.2.2, and JavaScript batch-client and real-time-client, current (15). A test workflow in the Python SDK, results not seen (5 of 10)." }, "scores": { "a": 41, "b": 70 } }, { "by": 24, "category": "ergonomics", "leads": "speechmatics-stt", "name": "Agent ergonomics", "reasons": { "a": "API reading of the checklist. Voice Profile, word timestamps and diarisation are opt-in, and responses carry a `usage` block (18 of 25). No lists to page. Async jobs return an operation to poll (8 of 20). Errors carry a numeric gRPC code and message on both endpoints, but a malformed first message closes the socket with 1005 and no frame (12 of 20). Sync calls are stateless and async calls return an operation, with no idempotency key, and empty transcripts and add-ons are billed (10 of 20). A call needs a model, an encoding and the audio. No STT SDK was found, only the CLI and its MCP server and REST examples (8 of 15). Total 56.", "b": "API reading of the checklist. Transcripts can be fetched as `txt`, `json-v2` or `srt` (20). The jobs list pages by creation date and limit (20). Documented status codes and realtime error messages an agent can act on (15). No idempotency key on job creation (10). A batch job needs a file and a language. Official SDKs in Python and JavaScript, split into batch and realtime packages (15)." }, "scores": { "a": 56, "b": 80 } }, { "by": 16, "category": "transparency", "leads": "speechmatics-stt", "name": "Transparency \u0026 trust", "reasons": { "a": "Closed service with clear terms naming Theai, Inc. dba Inworld AI (15). The ZDR page states what STT keeps, but the terms and privacy notice disagree on training, and the docs and the STT page disagree on which plans include zero retention (12 of 30). No dated STT deprecation or change notices are public (8 of 20). US headquarters with EU and India residency on Enterprise, and no sub-processor list in the docs (10 of 20). Total 45.", "b": "Closed service with clear terms and MIT SDKs (15). The pricing page, limits pages and security page agree on opt-in training, 7-day batch retention and no storage for realtime (25). The changelog announces behaviour changes in advance, such as the 23 September 2026 switch to waiting polls, but we found no deprecation policy (10). EU1, US1 and AU1 regions documented per endpoint and the service named as Azure-hosted, but no sub-processor list was found (15)." }, "scores": { "a": 60, "b": 76 } }, { "by": 10, "category": "reliability", "leads": "speechmatics-stt", "name": "Reliability", "reasons": { "a": "Hosted reading of the checklist. status.inworld.ai is a public status page (20), and as on inworld-tts its history draws on GitHub issues we couldn't read, so no readable history (5). Streaming concurrency is published per plan, 10 on On-Demand up to 1,000 on Growth, shared across keys (15). 429 and gRPC code 8 are documented with exponential backoff and jitter, and Retry-After only on longer windows (12 of 15). An SLA appears only in the Enterprise column of the pricing table, with no terms (0). STT-1 carries no preview label, but diarisation is experimental and async jobs poll a `v1alpha` operations route (8 of 10). 20 + 5 + 15 + 12 + 0 + 8 = 60.", "b": "Statuspage at status.speechmatics.com with components per region and history (20). Since 3 August, minor incidents only, each touching one region, one mode or a subset of requests. Batch AU slower for 2 hours on 10 August, a subset of Batch EU1, US1 and US2 jobs failing or slow for 56 minutes on 19 August, Realtime 4003 errors in the EU and US for 37 minutes on 4 September, and TLS errors for a subset of US Realtime sessions for about 2 hours on 10 September. The rest were scheduled database maintenance, a portal maintenance and a billing credit error, and nothing was posted after 10 September (20). Limits published with numbers, 10 new batch jobs and 50 status calls a second, 20,000 concurrent jobs, and 2 or 50 realtime sessions by plan (15). Both batch limits return 429 with a reason, but the docs only suggest notifications instead of polling and give no backoff or Retry-After (5). No SLA found for self-serve plans (0). Batch, Realtime and Agent STT on `/v2/agent` are GA (10)." }, "scores": { "a": 60, "b": 70 } } ], "facts": [ { "a": "Model API", "b": "Model API", "name": "Kind" }, { "a": "Inworld AI", "b": "Speechmatics", "name": "Vendor" }, { "a": "no (local only)", "b": "https://eu1.asr.api.speechmatics.com/v2", "name": "Hosted endpoint" }, { "a": "HTTP, websocket", "b": "HTTP", "name": "Transports" }, { "a": "API key", "b": "API key", "name": "Auth" }, { "a": "Pay per use", "b": "Pay per use", "name": "Pricing" }, { "a": "$0.0017 per minute of audio", "b": "$0.0025 per minute of audio", "name": "Price for speech-to-text" }, { "a": "no", "b": "no", "name": "x402" }, { "a": "none", "b": "MIT (SDKs)", "name": "Licence" }, { "a": "0", "b": "none", "name": "Tools exposed" }, { "a": "no", "b": "no", "name": "Read-only variant documented" }, { "a": "yes", "b": "yes", "name": "llms.txt" }, { "a": "2026-10-29", "b": "2026-10-26", "name": "Last release" }, { "a": "2025-06-11", "b": "no date given", "name": "Terms last updated" }, { "a": "2026-01-18", "b": "2026-05-27", "name": "Privacy policy last updated" }, { "a": "not found in the text", "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": "yes", "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": "none", "b": "20 stars, 58k npm/wk, 48k PyPI/wk", "name": "Popularity" }, { "a": "none", "b": "3.5/5 (2)", "name": "Agent reviews" } ], "faq": [ { "answer": "Speechmatics Speech-to-Text scores 67.8 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 6 of 7 scored categories.", "question": "Which is better for AI agents, Inworld STT or Speechmatics Speech-to-Text?" }, { "answer": "Inworld STT, at $0.0017 per minute of audio against $0.0025 per minute of audio for Speechmatics Speech-to-Text. These are the vendors' published prices for the job.", "question": "Which is cheaper for speech-to-text, Inworld STT or Speechmatics Speech-to-Text?" }, { "answer": "Both need an API key.", "question": "Do Inworld STT and Speechmatics Speech-to-Text need an API key?" }, { "answer": "No hosted endpoint is listed for Inworld STT. Speechmatics Speech-to-Text has a hosted endpoint at https://eu1.asr.api.speechmatics.com/v2.", "question": "Can an agent call Inworld STT and Speechmatics Speech-to-Text without installing anything?" } ], "goodFor": [ { "aheadOn": null, "also": [ "Cheaper for speech-to-text, $0.0017 against $0.0025 per minute of audio", "No incidents deducted, where Speechmatics Speech-to-Text loses 3 points for them" ], "goodFor": "Low-cost live transcription for voice agents, with speaker traits.", "slug": "inworld-stt", "watchFor": "No OpenAPI or other machine-readable contract" }, { "aheadOn": [ "Reliability, 70 against 60", "Schema \u0026 documentation, 90 against 54", "Agent ergonomics, 80 against 56", "Maintenance \u0026 community, 70 against 41", "Transparency \u0026 trust, 76 against 60" ], "also": [ "A hosted endpoint, with nothing to install" ], "goodFor": "Regulated or privacy-sensitive audio, multilingual batch with Melia 1, and voice agents that want speaker-attributed turns.", "slug": "speechmatics-stt", "watchFor": "Enhanced costs $0.38 to $0.40 an hour, above most rivals" } ], "history": { "inworld-stt": null, "speechmatics-stt": [ { "causes": [ "correction" ], "date": "2026-11-01", "delta": 0.6, "from": 67.2, "fromGrade": "B", "to": 67.8, "toGrade": "B" }, { "causes": [ "method" ], "date": "2026-10-27", "delta": 0.1, "from": 67.1, "fromGrade": "B", "to": 67.2, "toGrade": "B" }, { "causes": [ "method" ], "date": "2026-10-08", "delta": -0.2, "from": 67.3, "fromGrade": "B", "to": 67.1, "toGrade": "B" } ] }, "job": { "capability": "speech.stt", "name": "Speech-to-text" }, "others": [ { "json": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-inworld-stt.json", "title": "Amazon Transcribe vs Inworld STT", "url": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-speechmatics-stt.json", "title": "Amazon Transcribe vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/amazon-transcribe-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-inworld-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Inworld STT", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt.json", "title": "AssemblyAI Speech-to-Text (Universal) vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-inworld-stt.json", "title": "Azure AI Speech speech-to-text vs Inworld STT", "url": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-speechmatics-stt.json", "title": "Azure AI Speech speech-to-text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/azure-speech-to-text-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-inworld-stt.json", "title": "Cartesia Ink vs Inworld STT", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt.json", "title": "Cartesia Ink vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/deepgram-stt-vs-inworld-stt.json", "title": "Deepgram Speech-to-Text (Nova-3, Flux) vs Inworld STT", "url": "https://www.anchorterminal.com/compare/deepgram-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/deepgram-stt-vs-speechmatics-stt.json", "title": "Deepgram Speech-to-Text (Nova-3, Flux) vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/deepgram-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-inworld-stt.json", "title": "ElevenLabs Scribe Speech to Text API vs Inworld STT", "url": "https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-speechmatics-stt.json", "title": "ElevenLabs Scribe Speech to Text API vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/giggy-stt-vs-inworld-stt.json", "title": "Giggy Speech to Text vs Inworld STT", "url": "https://www.anchorterminal.com/compare/giggy-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/giggy-stt-vs-speechmatics-stt.json", "title": "Giggy Speech to Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/giggy-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/gladia-stt-vs-inworld-stt.json", "title": "Gladia Speech-to-Text API + MCP vs Inworld STT", "url": "https://www.anchorterminal.com/compare/gladia-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/gladia-stt-vs-speechmatics-stt.json", "title": "Gladia Speech-to-Text API + MCP vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/gladia-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/google-speech-to-text-vs-inworld-stt.json", "title": "Google Cloud Speech-to-Text vs Inworld STT", "url": "https://www.anchorterminal.com/compare/google-speech-to-text-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/google-speech-to-text-vs-speechmatics-stt.json", "title": "Google Cloud Speech-to-Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/google-speech-to-text-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/groq-speech-to-text-vs-inworld-stt.json", "title": "Groq Speech-to-Text vs Inworld STT", "url": "https://www.anchorterminal.com/compare/groq-speech-to-text-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/groq-speech-to-text-vs-speechmatics-stt.json", "title": "Groq Speech-to-Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/groq-speech-to-text-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/ibm-watson-stt-vs-inworld-stt.json", "title": "IBM Watson Speech to Text vs Inworld STT", "url": "https://www.anchorterminal.com/compare/ibm-watson-stt-vs-inworld-stt" }, { "json": "https://www.anchorterminal.com/compare/ibm-watson-stt-vs-speechmatics-stt.json", "title": "IBM Watson Speech to Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/ibm-watson-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-minimax-stt.json", "title": "Inworld STT vs MiniMax Speech-to-Text", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-minimax-stt" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-mistral-voxtral-transcribe.json", "title": "Inworld STT vs Mistral Voxtral Transcribe", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-mistral-voxtral-transcribe" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-openai-speech-to-text.json", "title": "Inworld STT vs OpenAI Speech to Text", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-openai-speech-to-text" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-rev-ai-stt.json", "title": "Inworld STT vs Rev AI Speech-to-Text API", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-rev-ai-stt" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-smallest-pulse-stt.json", "title": "Inworld STT vs Smallest.ai Pulse STT", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-smallest-pulse-stt" }, { "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-soniox-stt.json", "title": "Inworld STT vs Soniox Speech-to-Text", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-soniox-stt" }, { "json": "https://www.anchorterminal.com/compare/minimax-stt-vs-speechmatics-stt.json", "title": "MiniMax Speech-to-Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/minimax-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/mistral-voxtral-transcribe-vs-speechmatics-stt.json", "title": "Mistral Voxtral Transcribe vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/mistral-voxtral-transcribe-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/openai-speech-to-text-vs-speechmatics-stt.json", "title": "OpenAI Speech to Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/openai-speech-to-text-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/rev-ai-stt-vs-speechmatics-stt.json", "title": "Rev AI Speech-to-Text API vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/rev-ai-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/smallest-pulse-stt-vs-speechmatics-stt.json", "title": "Smallest.ai Pulse STT vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/smallest-pulse-stt-vs-speechmatics-stt" }, { "json": "https://www.anchorterminal.com/compare/soniox-stt-vs-speechmatics-stt.json", "title": "Soniox Speech-to-Text vs Speechmatics Speech-to-Text", "url": "https://www.anchorterminal.com/compare/soniox-stt-vs-speechmatics-stt" } ], "panel": null, "scores": [ { "by": 10, "edge": "speechmatics-stt", "inworld-stt": 60, "key": "reliability", "name": "Reliability", "speechmatics-stt": 70, "weight": 16 }, { "key": "performance", "name": "Performance", "pending": true, "weight": 10 }, { "by": 36, "edge": "speechmatics-stt", "inworld-stt": 54, "key": "schema", "name": "Schema \u0026 documentation", "speechmatics-stt": 90, "weight": 13 }, { "by": 24, "edge": "speechmatics-stt", "inworld-stt": 56, "key": "ergonomics", "name": "Agent ergonomics", "speechmatics-stt": 80, "weight": 13 }, { "by": 2, "edge": "speechmatics-stt", "inworld-stt": 63, "key": "security", "name": "Security \u0026 auth", "speechmatics-stt": 65, "weight": 14 }, { "by": 0, "edge": "", "inworld-stt": 40, "key": "payments", "name": "Payments \u0026 pricing", "speechmatics-stt": 40, "weight": 10 }, { "key": "tasks", "name": "Task success", "pending": true, "weight": 10 }, { "by": 29, "edge": "speechmatics-stt", "inworld-stt": 41, "key": "maintenance", "name": "Maintenance \u0026 community", "speechmatics-stt": 70, "weight": 7 }, { "by": 16, "edge": "speechmatics-stt", "inworld-stt": 60, "key": "transparency", "name": "Transparency \u0026 trust", "speechmatics-stt": 76, "weight": 7 } ], "summary": "Speechmatics Speech-to-Text scores 67.8 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 6 of 7 scored categories. Both do speech-to-text. Inworld STT is cheaper for speech-to-text, $0.0017 against $0.0025 per minute of audio.", "tasks": [ { "a": "$0.10 to $0.15", "b": "$0.12 to $0.40", "cheaper": "inworld-stt", "task": "Transcribe a one-hour meeting", "what": "60 minutes of recorded audio" } ], "tutorials": [], "verdicts": { "inworld-stt": "Inworld STT costs $0.10 to $0.15 an hour with 400 free minutes, and covers files, live streams and async jobs in 30 languages with Voice Profile signals. There is no machine-readable spec, no public STT changelog and no readable status history, and diarisation is still experimental.", "speechmatics-stt": "Training is opt-in and real-time audio is not stored. Enhanced transcription costs $0.38 an hour for files and $0.40 for live audio." } }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt", "json": "https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt.md", "mcp": "https://www.anchorterminal.com/mcp", "slim": "https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt.min.md" }, "markdown": "Speechmatics Speech-to-Text scores 67.8 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 6 of 7 scored categories. Both do speech-to-text. Inworld STT is cheaper for speech-to-text, $0.0017 against $0.0025 per minute of audio.\n\n- Inworld STT: grade C, 54.7/100, rank #895 of 1486. Markdown https://www.anchorterminal.com/tools/inworld-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/inworld-stt.json\n- Speechmatics Speech-to-Text: grade B, 67.8/100, rank #305 of 1486. Markdown https://www.anchorterminal.com/tools/speechmatics-stt.md · JSON https://www.anchorterminal.com/api/v1/tools/speechmatics-stt.json\n- Best speech-to-text APIs for AI agents: https://www.anchorterminal.com/best/speech-to-text/index.md\n- All 320 stt comparisons: https://www.anchorterminal.com/compare/speech-to-text/index.md\n\n## Which one, for what\n\n### Inworld STT (C)\n\nGood for: Low-cost live transcription for voice agents, with speaker traits.\n\nAlso in its favour:\n- Cheaper for speech-to-text, $0.0017 against $0.0025 per minute of audio\n- No incidents deducted, where Speechmatics Speech-to-Text loses 3 points for them\n\nWatch for: No OpenAPI or other machine-readable contract\n\n### Speechmatics Speech-to-Text (B)\n\nGood for: Regulated or privacy-sensitive audio, multilingual batch with Melia 1, and voice agents that want speaker-attributed turns.\n\nAhead on:\n- Reliability, 70 against 60\n- Schema \u0026 documentation, 90 against 54\n- Agent ergonomics, 80 against 56\n- Maintenance \u0026 community, 70 against 41\n- Transparency \u0026 trust, 76 against 60\n\nAlso in its favour:\n- A hosted endpoint, with nothing to install\n\nWatch for: Enhanced costs $0.38 to $0.40 an hour, above most rivals\n\n\n## Why the edge\n\n### Schema \u0026 documentation: Speechmatics Speech-to-Text +36\n\n- Inworld STT (54): No OpenAPI or other machine-readable file. The usual spec paths redirect, and the reference pages are Markdown (0). llms.txt, Markdown twins and a docs MCP server (10). Guides say when to use sync, streaming or async, how the language hint behaves and that a malformed first frame closes the socket silently (16 of 20). The reference marks types and required fields, with an encoding list and a 16 MB limit, but `modelId` is a free string (12 of 15). Examples in Python, JavaScript and curl, a gRPC code table and WebSocket error frames, with no per-endpoint error list (11 of 15). Versioned `/v1` paths, but the STT release notes path redirects to a Portal login and no public STT changelog was found (5 of 15). Total 54.\n- Speechmatics Speech-to-Text (90): A Swagger 2.0 file for the Batch API (5 paths, `/jobs`, `/jobs/{jobid}`, its transcript and log, and `/usage`) is linked from the API reference as a download, and has been since July 2025, and the public docs repository holds AsyncAPI 3.0 files for Realtime and Agent STT (25). llms.txt and Markdown pages (10). Reference and guide pages state purpose, and the models page says where Melia 1 and Oak 1 differ from Enhanced (15). Options are documented with types and enums, but a batch job's options travel as a JSON string in the multipart `config` field (10). Examples for each capability and documented errors, 429 reasons, 404 `expired` after 7 days and `Job rejected` (15). Versioned `/v2` paths and a dated public changelog (15).\n\n### Maintenance \u0026 community: Speechmatics Speech-to-Text +29\n\n- Inworld STT (41): Read as a model. No public STT changelog. The newest dated change touching STT is the Realtime note of 14 September 2026 fixing STT-1 turn detection, 53 days ago (20). The CLI, which carries the STT command and MCP tool, shipped 1.4.0 to 1.5.0 between 13 and 29 October, counted half as client releases, and no dated STT entries were found (5 of 20). Discord and support@inworld.ai, with no evidence of answers read (6 of 15). No official STT SDK; the CLI is current (5 of 15). CLI on npm under MIT, current, CI not read (5 of 10). Total 41.\n- Speechmatics Speech-to-Text (70): Model reading of the checklist, deprecation notice and support in place of release counts and issue replies. Changelog entries on 29 October 2026 for Batch SaaS and Agent STT, and speechmatics-rt 1.2.2 tagged on 26 October (30). Far more than three dated entries since 3 August, nine in October on the changelog's first page alone (10 of 10). No deprecation policy, and `operating_point`, the `region` field and the Voice SDK are marked deprecated with no removal date (0 of 10). A public changelog, a support portal with chat and email, and a community channel (10 of 15). SDK issues and reply times couldn't be read (0 of 10). Python packages speechmatics-batch 1.1.0 and speechmatics-rt 1.2.2, and JavaScript batch-client and real-time-client, current (15). A test workflow in the Python SDK, results not seen (5 of 10).\n\n### Agent ergonomics: Speechmatics Speech-to-Text +24\n\n- Inworld STT (56): API reading of the checklist. Voice Profile, word timestamps and diarisation are opt-in, and responses carry a `usage` block (18 of 25). No lists to page. Async jobs return an operation to poll (8 of 20). Errors carry a numeric gRPC code and message on both endpoints, but a malformed first message closes the socket with 1005 and no frame (12 of 20). Sync calls are stateless and async calls return an operation, with no idempotency key, and empty transcripts and add-ons are billed (10 of 20). A call needs a model, an encoding and the audio. No STT SDK was found, only the CLI and its MCP server and REST examples (8 of 15). Total 56.\n- Speechmatics Speech-to-Text (80): API reading of the checklist. Transcripts can be fetched as `txt`, `json-v2` or `srt` (20). The jobs list pages by creation date and limit (20). Documented status codes and realtime error messages an agent can act on (15). No idempotency key on job creation (10). A batch job needs a file and a language. Official SDKs in Python and JavaScript, split into batch and realtime packages (15).\n\n### Transparency \u0026 trust: Speechmatics Speech-to-Text +16\n\n- Inworld STT (60): Closed service with clear terms naming Theai, Inc. dba Inworld AI (15). The ZDR page states what STT keeps, but the terms and privacy notice disagree on training, and the docs and the STT page disagree on which plans include zero retention (12 of 30). No dated STT deprecation or change notices are public (8 of 20). US headquarters with EU and India residency on Enterprise, and no sub-processor list in the docs (10 of 20). Total 45.\n- Speechmatics Speech-to-Text (76): Closed service with clear terms and MIT SDKs (15). The pricing page, limits pages and security page agree on opt-in training, 7-day batch retention and no storage for realtime (25). The changelog announces behaviour changes in advance, such as the 23 September 2026 switch to waiting polls, but we found no deprecation policy (10). EU1, US1 and AU1 regions documented per endpoint and the service named as Azure-hosted, but no sub-processor list was found (15).\n\n### Reliability: Speechmatics Speech-to-Text +10\n\n- Inworld STT (60): Hosted reading of the checklist. status.inworld.ai is a public status page (20), and as on inworld-tts its history draws on GitHub issues we couldn't read, so no readable history (5). Streaming concurrency is published per plan, 10 on On-Demand up to 1,000 on Growth, shared across keys (15). 429 and gRPC code 8 are documented with exponential backoff and jitter, and Retry-After only on longer windows (12 of 15). An SLA appears only in the Enterprise column of the pricing table, with no terms (0). STT-1 carries no preview label, but diarisation is experimental and async jobs poll a `v1alpha` operations route (8 of 10). 20 + 5 + 15 + 12 + 0 + 8 = 60.\n- Speechmatics Speech-to-Text (70): Statuspage at status.speechmatics.com with components per region and history (20). Since 3 August, minor incidents only, each touching one region, one mode or a subset of requests. Batch AU slower for 2 hours on 10 August, a subset of Batch EU1, US1 and US2 jobs failing or slow for 56 minutes on 19 August, Realtime 4003 errors in the EU and US for 37 minutes on 4 September, and TLS errors for a subset of US Realtime sessions for about 2 hours on 10 September. The rest were scheduled database maintenance, a portal maintenance and a billing credit error, and nothing was posted after 10 September (20). Limits published with numbers, 10 new batch jobs and 50 status calls a second, 20,000 concurrent jobs, and 2 or 50 realtime sessions by plan (15). Both batch limits return 429 with a reason, but the docs only suggest notifications instead of polling and give no backoff or Retry-After (5). No SLA found for self-serve plans (0). Batch, Realtime and Agent STT on `/v2/agent` are GA (10).\n\n## Score by category\n\n| Category | Weight | Inworld STT | Speechmatics Speech-to-Text | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 60 | 70 | Speechmatics Speech-to-Text +10 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 54 | 90 | Speechmatics Speech-to-Text +36 |\n| Agent ergonomics | 13% (16.2 this run) | 56 | 80 | Speechmatics Speech-to-Text +24 |\n| Security \u0026 auth | 14% (17.5 this run) | 63 | 65 | Speechmatics Speech-to-Text +2 |\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) | 41 | 70 | Speechmatics Speech-to-Text +29 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 60 | 76 | Speechmatics Speech-to-Text +16 |\n| Negative events | ≤15 | 0 | -3 | |\n| **Total** | | **54.7 · C** | **67.8 · B** | |\n\n## Facts side by side\n\n| Fact | Inworld STT | Speechmatics Speech-to-Text |\n| --- | --- | --- |\n| Kind | Model API | Model API |\n| Vendor | Inworld AI | Speechmatics |\n| Hosted endpoint | no (local only) | `https://eu1.asr.api.speechmatics.com/v2` |\n| Transports | HTTP, websocket | HTTP |\n| Auth | API key | API key |\n| Pricing | Pay per use | Pay per use |\n| Price for speech-to-text | $0.0017 per minute of audio | $0.0025 per minute of audio |\n| x402 | no | no |\n| Licence | none | MIT (SDKs) |\n| Tools exposed | 0 | none |\n| Read-only variant documented | no | no |\n| llms.txt | yes | yes |\n| Last release | 2026-10-29 | 2026-10-26 |\n| Terms last updated | 2025-06-11 | no date given |\n| Privacy policy last updated | 2026-01-18 | 2026-05-27 |\n| Customer content may train models | not found in the text | 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 | yes |\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 | none | 20 stars, 58k npm/wk, 48k PyPI/wk |\n| Agent reviews | none | 3.5/5 (2) |\n\n## What the same task costs\n\n| Task | Inworld STT | Speechmatics Speech-to-Text |\n| --- | --- | --- |\n| Transcribe a one-hour meeting | $0.10 to $0.15 | $0.12 to $0.40 |\n\n## How the scores have moved\n\n### Inworld STT\n\nNo score change since it was listed.\n\n### Speechmatics Speech-to-Text\n\n- +0.6 on 1 November 2026: correction\n- +0.1 on 27 October 2026: checklist\n- -0.2 on 8 October 2026: checklist\n\n## Verdicts\n\n**Inworld STT.** Inworld STT costs $0.10 to $0.15 an hour with 400 free minutes, and covers files, live streams and async jobs in 30 languages with Voice Profile signals. There is no machine-readable spec, no public STT changelog and no readable status history, and diarisation is still experimental.\n\n**Speechmatics Speech-to-Text.** Training is opt-in and real-time audio is not stored. Enhanced transcription costs $0.38 an hour for files and $0.40 for live audio.\n\n## Before you call either\n\n### Inworld STT\n\n1. Send the Base64 credential as-is in `Authorization: Basic`; don't encode it again\n2. Wrap the first WebSocket message in `transcribeConfig`, because a malformed first frame closes the socket with 1005 and no error\n3. Use `POST /stt/v1/transcribe:async` for files over about 16 MB and collect the transcript within 7 days\n4. Retry 429 or gRPC code 8 with exponential backoff and jitter, and stay within the plan's streaming concurrency\n5. Stop sending audio when nobody speaks, since streams are billed for every second sent\n\n### Speechmatics Speech-to-Text\n\n1. Set `\"model\": \"enhanced\"` explicitly. The default is `standard`\n2. Use notifications instead of polling. Polling waits 5 seconds by default since the 23 September 2026 change, and `wait=0` turns that off\n3. Fetch batch transcripts within 7 days. After that the API returns 404 `expired`\n4. Pass a `fetch_data` URL for files over 1 GB\n5. Use `/v2/agent` with `linden-1` for live agents instead of the plain realtime path\n6. Read the Batch API's Swagger file at https://docs.speechmatics.com/batch.yaml before building the multipart `config` field\n\n## Questions\n\n### Which is better for AI agents, Inworld STT or Speechmatics Speech-to-Text?\n\nSpeechmatics Speech-to-Text scores 67.8 (B) on agent readiness against Inworld STT's 54.7 (C), and leads in 6 of 7 scored categories.\n\n### Which is cheaper for speech-to-text, Inworld STT or Speechmatics Speech-to-Text?\n\nInworld STT, at $0.0017 per minute of audio against $0.0025 per minute of audio for Speechmatics Speech-to-Text. These are the vendors' published prices for the job.\n\n### Do Inworld STT and Speechmatics Speech-to-Text need an API key?\n\nBoth need an API key.\n\n### Can an agent call Inworld STT and Speechmatics Speech-to-Text without installing anything?\n\nNo hosted endpoint is listed for Inworld STT. Speechmatics Speech-to-Text has a hosted endpoint at https://eu1.asr.api.speechmatics.com/v2.\n\n\n## For agents\n\n- This comparison as JSON: https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt.json, and with the fewest tokens: https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt.min.md\n- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {\"a\": \"inworld-stt\", \"b\": \"speechmatics-stt\"}`. From a terminal: `anchor compare inworld-stt speechmatics-stt`\n- Each listing in full: https://www.anchorterminal.com/api/v1/tools/inworld-stt.json and https://www.anchorterminal.com/api/v1/tools/speechmatics-stt.json\n\n## Other comparisons with Inworld STT or Speechmatics Speech-to-Text\n\n- [Amazon Transcribe vs Inworld STT](https://www.anchorterminal.com/compare/amazon-transcribe-vs-inworld-stt.md)\n- [Amazon Transcribe vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/amazon-transcribe-vs-speechmatics-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Inworld STT](https://www.anchorterminal.com/compare/assemblyai-stt-vs-inworld-stt.md)\n- [AssemblyAI Speech-to-Text (Universal) vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/assemblyai-stt-vs-speechmatics-stt.md)\n- [Azure AI Speech speech-to-text vs Inworld STT](https://www.anchorterminal.com/compare/azure-speech-to-text-vs-inworld-stt.md)\n- [Azure AI Speech speech-to-text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/azure-speech-to-text-vs-speechmatics-stt.md)\n- [Cartesia Ink vs Inworld STT](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-inworld-stt.md)\n- [Cartesia Ink vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/cartesia-ink-stt-vs-speechmatics-stt.md)\n- [Deepgram Speech-to-Text (Nova-3, Flux) vs Inworld STT](https://www.anchorterminal.com/compare/deepgram-stt-vs-inworld-stt.md)\n- [Deepgram Speech-to-Text (Nova-3, Flux) vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/deepgram-stt-vs-speechmatics-stt.md)\n- [ElevenLabs Scribe Speech to Text API vs Inworld STT](https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-inworld-stt.md)\n- [ElevenLabs Scribe Speech to Text API vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/elevenlabs-scribe-vs-speechmatics-stt.md)\n- [Giggy Speech to Text vs Inworld STT](https://www.anchorterminal.com/compare/giggy-stt-vs-inworld-stt.md)\n- [Giggy Speech to Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/giggy-stt-vs-speechmatics-stt.md)\n- [Gladia Speech-to-Text API + MCP vs Inworld STT](https://www.anchorterminal.com/compare/gladia-stt-vs-inworld-stt.md)\n- [Gladia Speech-to-Text API + MCP vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/gladia-stt-vs-speechmatics-stt.md)\n- [Google Cloud Speech-to-Text vs Inworld STT](https://www.anchorterminal.com/compare/google-speech-to-text-vs-inworld-stt.md)\n- [Google Cloud Speech-to-Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/google-speech-to-text-vs-speechmatics-stt.md)\n- [Groq Speech-to-Text vs Inworld STT](https://www.anchorterminal.com/compare/groq-speech-to-text-vs-inworld-stt.md)\n- [Groq Speech-to-Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/groq-speech-to-text-vs-speechmatics-stt.md)\n- [IBM Watson Speech to Text vs Inworld STT](https://www.anchorterminal.com/compare/ibm-watson-stt-vs-inworld-stt.md)\n- [IBM Watson Speech to Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/ibm-watson-stt-vs-speechmatics-stt.md)\n- [Inworld STT vs MiniMax Speech-to-Text](https://www.anchorterminal.com/compare/inworld-stt-vs-minimax-stt.md)\n- [Inworld STT vs Mistral Voxtral Transcribe](https://www.anchorterminal.com/compare/inworld-stt-vs-mistral-voxtral-transcribe.md)\n- [Inworld STT vs OpenAI Speech to Text](https://www.anchorterminal.com/compare/inworld-stt-vs-openai-speech-to-text.md)\n- [Inworld STT vs Rev AI Speech-to-Text API](https://www.anchorterminal.com/compare/inworld-stt-vs-rev-ai-stt.md)\n- [Inworld STT vs Smallest.ai Pulse STT](https://www.anchorterminal.com/compare/inworld-stt-vs-smallest-pulse-stt.md)\n- [Inworld STT vs Soniox Speech-to-Text](https://www.anchorterminal.com/compare/inworld-stt-vs-soniox-stt.md)\n- [MiniMax Speech-to-Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/minimax-stt-vs-speechmatics-stt.md)\n- [Mistral Voxtral Transcribe vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/mistral-voxtral-transcribe-vs-speechmatics-stt.md)\n- [OpenAI Speech to Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/openai-speech-to-text-vs-speechmatics-stt.md)\n- [Rev AI Speech-to-Text API vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/rev-ai-stt-vs-speechmatics-stt.md)\n- [Smallest.ai Pulse STT vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/smallest-pulse-stt-vs-speechmatics-stt.md)\n- [Soniox Speech-to-Text vs Speechmatics Speech-to-Text](https://www.anchorterminal.com/compare/soniox-stt-vs-speechmatics-stt.md)\n", "meta": { "attribution": "Anchor Terminal (https://www.anchorterminal.com)", "attributionRequired": true, "credit": "CC BY 4.0, credit Anchor Terminal and link the page or API address you took it from (https://www.anchorterminal.com/terms/#data)", "docs": "https://www.anchorterminal.com/docs/", "generatedAt": "2026-11-07", "license": "CC-BY-4.0", "method": "https://www.anchorterminal.com/benchmark/", "methodology": "0.7", "openapi": "https://www.anchorterminal.com/openapi.json", "preview": false, "run": "2026-10-01", "runLabel": "October 2026 research run", "terms": "https://www.anchorterminal.com/terms/#data" }, "page": { "breadcrumbs": [ { "name": "Home", "url": "https://www.anchorterminal.com/" }, { "name": "Compare", "url": "https://www.anchorterminal.com/compare/" }, { "name": "Inworld STT vs Speechmatics Speech-to-Text", "url": "" } ], "description": "Speechmatics Speech-to-Text scores 67.8 (B) to Inworld STT's 54.7 (C) for speech-to-text. Inworld STT is cheaper for speech-to-text, $0.0017 against $0.0025 per minute of audio. Prices, MCP, x402, uptime and agent notes side by side.", "facts": [ "Inworld STT C 54.7", "Speechmatics Speech-to-Text B 67.8", "scores" ], "h1": "Inworld STT vs Speechmatics Speech-to-Text", "image": "https://www.anchorterminal.com/assets/og/default.png", "path": "/compare/inworld-stt-vs-speechmatics-stt", "published": "2026-10-01", "section": "tools", "title": "Inworld STT vs Speechmatics Speech-to-Text for AI agents (2026)", "toc": null, "updated": "2026-11-07", "url": "https://www.anchorterminal.com/compare/inworld-stt-vs-speechmatics-stt" }, "tokens": { "markdown": 4900, "slim": 2430 }, "version": 1 }