{ "data": { "a": { "slug": "bandwidth-voice", "name": "Bandwidth Voice API + MCP", "vendor": "Bandwidth", "vendorUrl": "https://www.bandwidth.com", "kind": "http-api", "category": "voice-calling", "summary": "Programmable voice on Bandwidth's own US carrier network, with BXML call control, bidirectional WebSocket media streams, recording, transcription and transfers.", "url": "https://www.anchorterminal.com/tools/bandwidth-voice", "markdownUrl": "https://www.anchorterminal.com/tools/bandwidth-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/bandwidth-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/bandwidth-voice.json", "repo": "https://github.com/Bandwidth/mcp-server", "transports": [ "http", "stdio", "streamable-http" ], "remoteUrl": "https://voice.bandwidth.com/api/v2", "packages": [ { "registry": "npm", "name": "bandwidth-sdk" }, { "registry": "pypi", "name": "bandwidth-sdk" } ], "auth": "oauth", "authNotes": "OAuth 2.0 client credentials. Exchange the client ID and secret at api.bandwidth.com/api/v1/oauth2/token for a Bearer token. Legacy Basic-auth API users are being migrated. The MCP server takes BW_CLIENT_ID and BW_CLIENT_SECRET.", "pricing": "usage", "pricingNotes": "Free Build trial with 3,000 credits, a US number and no card, then pay as you go. US local outbound $0.01 and inbound $0.0055 a minute. Recording $0.002 a minute, transcription $0.045 standard or $0.0451 real time, media streaming $0.0035 one-way or $0.004 bidirectional. Number rental and SIP trunking are quoted by sales (https://www.bandwidth.com/pricing/).", "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": 2, "npmWeekly": 12740, "pypiWeekly": 39218, "asOf": "2026-09-30" }, "docsUrl": "https://dev.bandwidth.com/docs/voice", "llmsTxt": "https://dev.bandwidth.com/llms.txt", "openapi": "https://dev.bandwidth.com/spec/voice.yml", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "no-card", "mcp", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming" ], "lastRelease": "2026-09-22", "graded": true, "anchor": { "graded": true, "score": 63.7, "grade": "B", "agentReady": false, "rank": 196, "ranked": true, "rankOf": 452, "categoryRank": 4, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 65, "maintenance": 78, "payments": 35, "reliability": 58, "schema": 88, "security": 60, "transparency": 63 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "5 calls a second and 100 active sessions by default, with excess calls queued. Number rental and SIP trunking prices aren't published.", "strengths": [ "5 calls a second and 100 active sessions by default, with excess calls queued", "No-card Build trial with 3,000 credits, a US number and SIP trunking", "OAuth 2.0 client credentials with 1-hour tokens, per-credential roles and secret rotation", "OpenAPI spec and llms.txt with Markdown pages", "Per-call debug logs with API request history and webhook delivery attempts" ], "weaknesses": [ "Number rental and SIP trunking prices aren't published", "No bug bounty, security.txt or callback signing found", "LAX and JFK datacentre incidents hit voice for about 7 and 5 hours in August", "No Retry-After or backoff guidance on 429", "MCP server is beta, installed by git clone, with no licence file" ], "agentNotes": [ "Get a token from the OAuth endpoint first, then POST to /accounts/{accountId}/calls with an applicationId and answerUrl", "Keep the call alive with Pause or a redirect while a bidirectional stream runs, or it hangs up when BXML runs out", "Read the 429 message to tell a rate limit from a concurrency limit before retrying", "Load the MCP server with BW_MCP_PROFILE=voice to keep the tool list short" ], "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": 63.7 } ], "editorialScores": { "ergonomics": 65, "maintenance": 78, "payments": 35, "reliability": 58, "schema": 88, "security": 60, "transparency": 35 }, "provenanceScore": 90 }, "connect": { "http": "curl -X POST \"https://voice.bandwidth.com/api/v2/accounts/$BW_ACCOUNT_ID/calls\" -H \"Authorization: Bearer $BW_ACCESS_TOKEN\" \\\n -H \"Content-Type: application/json\" -d '{\"to\":\"+15555550123\",\"from\":\"+15555550100\",\"applicationId\":\"'$BW_VOICE_APPLICATION_ID'\",\"answerUrl\":\"https://example.com/answer\"}'", "config": { "mcpServers": { "bandwidth": { "args": [ "--from", "/path/to/mcp-server", "start" ], "command": "uvx", "env": { "BW_ACCOUNT_ID": "${BW_ACCOUNT_ID}", "BW_CLIENT_ID": "${BW_CLIENT_ID}", "BW_CLIENT_SECRET": "${BW_CLIENT_SECRET}", "BW_MCP_PROFILE": "voice" } } } } }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/bandwidth-voice" }, "sameCompany": [ "bandwidth" ], "area": "voice", "unitPrices": [ { "item": "US outbound, local", "unit": "call-minute", "usd": 0.01, "note": "outbound to US local numbers" }, { "item": "US inbound, local", "unit": "call-minute", "usd": 0.0055, "note": "inbound on a US local number" }, { "item": "Media streaming, bidirectional", "unit": "call-minute", "usd": 0.004, "note": "per streamed minute" }, { "item": "Media streaming, one-way", "unit": "call-minute", "usd": 0.0035, "note": "per streamed minute" }, { "item": "Recording", "unit": "call-minute", "usd": 0.002, "note": "per recorded minute" } ], "provenance": { "legalEntity": "Bandwidth Inc.", "domain": "bandwidth.com", "domainRegistered": "1995-02-20", "endpointOnVendorDomain": true, "terms": "https://www.bandwidth.com/legal/communications-services-agreement/", "privacy": "https://www.bandwidth.com/legal/privacy/", "statusPage": "https://status.bandwidth.com", "changelog": "https://www.bandwidth.com/release-notes/", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "Provenance shared with the Bandwidth messaging listing." ], "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/bandwidth-voice.json", "live": { "slug": "bandwidth-voice", "probe": { "target": "https://voice.bandwidth.com/api/v2", "method": "get", "lastAt": "2026-10-04T23:48:04.856079568Z", "lastOk": true, "lastStatus": 403, "lastMs": 60, "lastNote": "asks for credentials", "authRequired": true, "uptime24h": 100, "uptime30d": 100, "p50ms24h": 61, "p95ms24h": 123, "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.bandwidth.com", "indicator": "maintenance", "summary": "Service Under Maintenance", "checkedAt": "2026-10-04T23:49:06.131843339Z" }, "versions": [ { "registry": "github", "name": "Bandwidth/mcp-server", "version": "v0.3.0", "released": "2026-06-11", "seenAt": "2026-10-04T16:21:51.875806743Z" }, { "registry": "npm", "name": "bandwidth-sdk", "version": "8.3.0", "seenAt": "2026-10-04T16:21:51.254649229Z" }, { "registry": "pypi", "name": "bandwidth-sdk", "version": "23.3.0", "released": "2026-09-22", "seenAt": "2026-10-04T16:21:51.689982393Z" } ], "githubStars": 2, "npmWeekly": 14503, "pypiWeekly": 35330, "securityTxt": { "url": "https://bandwidth.com/.well-known/security.txt", "state": "unknown", "checkedAt": "2026-10-04T15:16:04.580175049Z" }, "llmsTxt": { "url": "https://dev.bandwidth.com/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:17:18.684718216Z" }, "domain": { "domain": "bandwidth.com", "registered": "1995-02-20", "source": "https://rdap.verisign.com/com/v1/domain/bandwidth.com", "checkedAt": "2026-10-04T13:08:39.296680691Z" }, "pages": [ { "url": "https://www.bandwidth.com/release-notes/", "kind": "changelog", "status": 200, "checkedAt": "2026-10-04T15:49:23.983694909Z", "changedAt": "2026-10-03T15:37:19.430596463Z", "fingerprint": "87b32035924b" }, { "url": "https://www.bandwidth.com/pricing/", "kind": "pricing", "status": 200, "checkedAt": "2026-10-04T15:49:21.980288465Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "b3b61701939e" }, { "url": "https://www.bandwidth.com/legal/privacy/", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:49:20.642543658Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "e0e2641969a7" }, { "url": "https://www.bandwidth.com/legal/communications-services-agreement/", "kind": "terms", "status": 200, "checkedAt": "2026-10-04T15:49:17.739941299Z", "changedAt": "2026-10-04T15:49:17.739941299Z", "fingerprint": "2b4532228e6f" } ], "updatedAt": "2026-10-04T23:49:06.131843339Z" } }, "b": { "slug": "signalwire-voice", "name": "SignalWire Voice API", "vendor": "SignalWire", "vendorUrl": "https://signalwire.com", "kind": "http-api", "category": "voice-calling", "summary": "Programmable calling API from the team behind FreeSWITCH.", "url": "https://www.anchorterminal.com/tools/signalwire-voice", "markdownUrl": "https://www.anchorterminal.com/tools/signalwire-voice.md", "slimMarkdownUrl": "https://www.anchorterminal.com/tools/signalwire-voice.min.md", "jsonUrl": "https://www.anchorterminal.com/api/v1/tools/signalwire-voice.json", "repo": "https://github.com/signalwire/signalwire-python", "license": "MIT", "transports": [ "http" ], "packages": [ { "registry": "pypi", "name": "signalwire-sdk" }, { "registry": "npm", "name": "@signalwire/sdk" }, { "registry": "pypi", "name": "signalwire" } ], "auth": "api-key", "authNotes": "HTTP Basic auth with the Project ID and an API token, scoped per product (the Voice scope for calls). Each account has its own Space subdomain, so the host differs per customer. New tokens start with swapi_ since September 2026.", "pricing": "usage", "pricingNotes": "Pay as you go. New accounts start in trial mode without a card, and adding a card with at least $5 of credit lifts the restrictions. US local inbound $0.0066 and outbound $0.008 a minute, toll-free inbound $0.0147 and outbound $0.0069, SIP or WebRTC legs $0.003. Local numbers $0.50 a month, toll-free $0.80. Recording $0.002 a minute, live transcription $0.065 a minute per direction, and the AI agent runtime $0.16 a minute including STT, LLM and standard TTS (https://www.signalwire.com/pricing/voice).", "priceSummary": "$0.50 / mo", "where": "local", "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": 8, "npmWeekly": 1531, "pypiWeekly": 1349, "asOf": "2026-09-30" }, "docsUrl": "https://signalwire.com/docs/platform/voice", "llmsTxt": "https://signalwire.com/docs/llms.txt", "openapi": "https://signalwire.com/docs/openapi.json", "capabilities": [ "voice.calls", "voice.numbers", "voice.streaming", "voice.sip", "voice.recording", "voice.transfer" ], "tags": [ "hosted", "llms-txt", "openapi", "typescript", "python", "webhooks", "streaming" ], "lastRelease": "2026-09-30", "graded": true, "anchor": { "graded": true, "score": 67.3, "grade": "B", "agentReady": false, "rank": 144, "ranked": true, "rankOf": 452, "categoryRank": 3, "methodology": "0.3", "run": "2026-10-01", "scores": { "ergonomics": 68, "maintenance": 81, "payments": 40, "reliability": 53, "schema": 87, "security": 72, "transparency": 78 }, "pending": [ "performance", "tasks" ], "assessment": { "confidence": "medium", "date": "2026-10-01" }, "negative": 0, "verdict": "SWML documents, REST commands and a Relay WebSocket client for call control. Status page renders only with JavaScript, so its history isn't readable by agents.", "strengths": [ "SWML documents, REST commands and a Relay WebSocket client for call control", "OpenAPI 3.1 spec and Markdown for every docs page", "SLA of 99.95 per cent monthly uptime on every account, plus ISO 27001, SOC 2 Type 2, a DPA and a disclosure policy", "Webhooks signed with HMAC in `x-signalwire-signature`, checked by the Python SDK on SWML and tool calls", "Six Python SDK releases between 25 August and 29 September 2026" ], "weaknesses": [ "Status page renders only with JavaScript, so its history isn't readable by agents", "No published rate-limit numbers beyond the trial's 10 queued calls", "No idempotency key, and the safe-retry rules live in the Python SDK rather than the API docs", "Per-customer Space hostnames, so there is no single public API host", "No security.txt or bug bounty" ], "agentNotes": [ "Send dial with a url pointing at a SWML document, then use calling.* commands on the returned call ID", "Don't retry a dial on a 5xx. Retry only on 429 or 503, after Retry-After, or you may place the call twice", "Use your own Space subdomain as the host, there is no shared API host", "Create a token with only the Voice scope for a calling agent", "Verify `x-signalwire-signature` with the Signing Key before acting on a webhook" ], "metrics": { "kind": "remote", "measured": false }, "reviewCount": 2, "avgRating": 3.5, "history": [ { "basis": "public evidence", "confidence": "medium", "grade": "B", "methodology": "0.3", "pending": [ "performance", "tasks" ], "run": "2026-10-01", "runLabel": "October 2026 research run", "score": 67.3 } ], "editorialScores": { "ergonomics": 68, "maintenance": 81, "payments": 40, "reliability": 53, "schema": 87, "security": 72, "transparency": 65 }, "provenanceScore": 90 }, "connect": { "http": "curl -X POST \"https://$SIGNALWIRE_SPACE.signalwire.com/api/calling/calls\" -u \"$SIGNALWIRE_PROJECT_ID:$SIGNALWIRE_API_TOKEN\" \\\n -H \"Content-Type: application/json\" -d '{\"command\":\"dial\",\"params\":{\"from\":\"+15551234567\",\"to\":\"+15557654321\",\"url\":\"https://example.com/swml\"}}'" }, "letme": { "capability": "https://letme.dev/voice.calls", "tool": "https://letme.dev/signalwire-voice" }, "area": "voice", "unitPrices": [ { "item": "US outbound, local", "unit": "call-minute", "usd": 0.008, "note": "outbound to US local numbers" }, { "item": "US inbound, local number", "unit": "call-minute", "usd": 0.0066, "note": "inbound on a US local number" }, { "item": "US outbound, toll-free", "unit": "call-minute", "usd": 0.0069, "note": "outbound to US toll-free numbers" }, { "item": "US inbound, toll-free number", "unit": "call-minute", "usd": 0.0147, "note": "inbound on a US toll-free number" }, { "item": "SIP or WebRTC leg", "unit": "call-minute", "usd": 0.003, "note": "inbound or outbound" }, { "item": "AI agent runtime", "unit": "call-minute", "usd": 0.16, "note": "platform fee on top of call minutes, includes STT, LLM and standard TTS" }, { "item": "US local number", "unit": "month", "usd": 0.5, "note": "per number" }, { "item": "US toll-free number", "unit": "month", "usd": 0.8, "note": "per number" } ], "provenance": { "legalEntity": "SignalWire, Inc.", "domain": "signalwire.com", "domainRegistered": "2016-01-21", "endpointOnVendorDomain": true, "terms": "https://info.signalwire.com/hubfs/PDFs/SignalWire-Cloud-Agreement.pdf", "privacy": "https://m.signalwire.com/policies?doc=privacy", "statusPage": "https://status.signalwire.com", "changelog": "https://signalwire.com/docs/platform/changelog", "securityTxt": "none", "checked": "2026-09-30", "notes": [ "Legal entity from signalwire.com/legal. The status page redirects to a PagerDuty-hosted page.", "remoteUrl left empty because each account calls its own Space subdomain (\u003cspace\u003e.signalwire.com/api/calling/calls)." ], "score": 90 }, "pageJsonUrl": "https://www.anchorterminal.com/tools/signalwire-voice.json", "live": { "slug": "signalwire-voice", "vendorStatus": { "page": "https://status.signalwire.com", "indicator": "unknown", "summary": "no machine-readable status found", "checkedAt": "2026-10-04T21:40:28.923320603Z" }, "versions": [ { "registry": "github", "name": "signalwire/signalwire-python", "version": "v3.5.1", "released": "2026-09-29", "seenAt": "2026-10-04T16:39:55.315839064Z" }, { "registry": "npm", "name": "@signalwire/sdk", "version": "3.5.0", "seenAt": "2026-10-04T16:39:53.193390994Z" }, { "registry": "pypi", "name": "signalwire", "version": "2.1.1", "released": "2025-02-04", "seenAt": "2026-10-04T16:39:55.23247842Z" }, { "registry": "pypi", "name": "signalwire-sdk", "version": "3.5.1", "released": "2026-09-29", "seenAt": "2026-10-04T16:39:53.002324781Z" } ], "githubStars": 8, "npmWeekly": 2180, "pypiWeekly": 873, "securityTxt": { "url": "https://signalwire.com/.well-known/security.txt", "state": "none", "checkedAt": "2026-10-04T15:15:52.668431076Z" }, "llmsTxt": { "url": "https://signalwire.com/docs/llms.txt", "ok": true, "status": 200, "checkedAt": "2026-10-04T15:18:14.357836072Z" }, "domain": { "domain": "signalwire.com", "registered": "2016-01-21", "source": "https://rdap.verisign.com/com/v1/domain/signalwire.com", "checkedAt": "2026-10-04T13:04:21.502174122Z" }, "pages": [ { "url": "https://signalwire.com/docs/platform/changelog", "kind": "deprecations", "status": 304, "checkedAt": "2026-10-04T15:47:48.382944869Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "da8a160eb045" }, { "url": "https://www.signalwire.com/pricing/voice", "kind": "pricing", "status": 304, "checkedAt": "2026-10-04T15:52:14.172315609Z", "changedAt": "2026-10-03T15:40:04.301482046Z", "fingerprint": "40b5008528b4" }, { "url": "https://m.signalwire.com/policies?doc=privacy", "kind": "privacy", "status": 200, "checkedAt": "2026-10-04T15:45:46.511500727Z", "changedAt": "0001-01-01T00:00:00Z", "fingerprint": "e3b0c44298fc" } ], "updatedAt": "2026-10-04T21:40:28.923320603Z" } }, "summary": "SignalWire Voice API has a score of 67.3 (B) against Bandwidth Voice API + MCP's 63.7 (B). Both do voice calls. The largest gap is transparency \u0026 trust, 15 points." }, "kind": "anchor.page", "links": { "api": "https://www.anchorterminal.com/api/v1/index.json", "html": "https://www.anchorterminal.com/compare/bandwidth-voice-vs-signalwire-voice", "json": "https://www.anchorterminal.com/compare/bandwidth-voice-vs-signalwire-voice.json", "llms": "https://www.anchorterminal.com/llms.txt", "markdown": "https://www.anchorterminal.com/compare/bandwidth-voice-vs-signalwire-voice.md", "slim": "https://www.anchorterminal.com/compare/bandwidth-voice-vs-signalwire-voice.min.md" }, "markdown": "SignalWire Voice API has a score of 67.3 (B) against Bandwidth Voice API + MCP's 63.7 (B). Both do voice calls. The largest gap is transparency \u0026 trust, 15 points.\n\n- Bandwidth Voice API + MCP: grade B, 63.7/100, rank #196 of 452. Markdown https://www.anchorterminal.com/tools/bandwidth-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/bandwidth-voice.json\n- SignalWire Voice API: grade B, 67.3/100, rank #144 of 452. Markdown https://www.anchorterminal.com/tools/signalwire-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/signalwire-voice.json\n\n## Which one, for what\n\nPick Bandwidth Voice API + MCP for reliability (+5).\n\nPick SignalWire Voice API for security \u0026 auth (+12), payments \u0026 pricing (+5), transparency \u0026 trust (+15).\n\n## Score by category\n\n| Category | Weight | Bandwidth Voice API + MCP | SignalWire Voice API | Edge |\n| --- | --- | --- | --- | --- |\n| Reliability | 16% (20 this run) | 58 | 53 | Bandwidth Voice API + MCP +5 |\n| Performance | 10%, pending | pending | pending | not scored in this run |\n| Schema \u0026 documentation | 13% (16.2 this run) | 88 | 87 | Bandwidth Voice API + MCP +1 |\n| Agent ergonomics | 13% (16.2 this run) | 65 | 68 | SignalWire Voice API +3 |\n| Security \u0026 auth | 14% (17.5 this run) | 60 | 72 | SignalWire Voice API +12 |\n| Payments \u0026 pricing | 10% (12.5 this run) | 35 | 40 | SignalWire Voice API +5 |\n| Task success | 10%, pending | pending | pending | not scored in this run |\n| Maintenance \u0026 community | 7% (8.8 this run) | 78 | 81 | SignalWire Voice API +3 |\n| Transparency \u0026 trust | 7% (8.8 this run) | 63 | 78 | SignalWire Voice API +15 |\n| Negative events | ≤15 | 0 | 0 | |\n| **Total** | | **63.7 · B** | **67.3 · B** | |\n\n## Facts side by side\n\n| Fact | Bandwidth Voice API + MCP | SignalWire Voice API |\n| --- | --- | --- |\n| Kind | HTTP API | HTTP API |\n| Vendor | Bandwidth | SignalWire |\n| Hosted endpoint | `https://voice.bandwidth.com/api/v2` | no (local only) |\n| Transports | HTTP, stdio, Streamable HTTP | HTTP |\n| Auth | OAuth | API key |\n| Pricing | Pay per use | Pay per use |\n| x402 | no | no |\n| Licence | none | MIT |\n| Tools exposed | none | none |\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 | not listed |\n| Last release | 2026-09-22 | 2026-09-30 |\n| Popularity | 2 stars, 13k npm/wk, 39k PyPI/wk | 8 stars, 1.5k npm/wk, 1.3k PyPI/wk |\n| Agent reviews | 3/5 (2) | 3.5/5 (2) |\n\n## Verdicts\n\n**Bandwidth Voice API + MCP.** 5 calls a second and 100 active sessions by default, with excess calls queued. Number rental and SIP trunking prices aren't published.\n\n**SignalWire Voice API.** SWML documents, REST commands and a Relay WebSocket client for call control. Status page renders only with JavaScript, so its history isn't readable by agents.\n\n## Before you call either\n\n### Bandwidth Voice API + MCP\n\n1. Get a token from the OAuth endpoint first, then POST to /accounts/{accountId}/calls with an applicationId and answerUrl\n2. Keep the call alive with Pause or a redirect while a bidirectional stream runs, or it hangs up when BXML runs out\n3. Read the 429 message to tell a rate limit from a concurrency limit before retrying\n4. Load the MCP server with BW_MCP_PROFILE=voice to keep the tool list short\n\n### SignalWire Voice API\n\n1. Send dial with a url pointing at a SWML document, then use calling.* commands on the returned call ID\n2. Don't retry a dial on a 5xx. Retry only on 429 or 503, after Retry-After, or you may place the call twice\n3. Use your own Space subdomain as the host, there is no shared API host\n4. Create a token with only the Voice scope for a calling agent\n5. Verify `x-signalwire-signature` with the Signing Key before acting on a webhook\n\n## Other comparisons with Bandwidth Voice API + MCP or SignalWire Voice API\n\n- [Bandwidth Voice API + MCP vs Exotel Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-exotel-voice.md)\n- [Bandwidth Voice API + MCP vs Infobip Calls API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-infobip-calls.md)\n- [Bandwidth Voice API + MCP vs Plivo Voice API](https://www.anchorterminal.com/compare/bandwidth-voice-vs-plivo-voice.md)\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- [Bandwidth Voice API + MCP vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-twilio-voice.md)\n- [Bandwidth Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-vonage-voice.md)\n- [Bandwidth Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/bandwidth-voice-vs-voximplant.md)\n- [Exotel Voice API + MCP vs SignalWire Voice API](https://www.anchorterminal.com/compare/exotel-voice-vs-signalwire-voice.md)\n- [Infobip Calls API + MCP vs SignalWire Voice API](https://www.anchorterminal.com/compare/infobip-calls-vs-signalwire-voice.md)\n- [Plivo Voice API vs SignalWire Voice API](https://www.anchorterminal.com/compare/plivo-voice-vs-signalwire-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- [SignalWire Voice API vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-twilio-voice.md)\n- [SignalWire Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-vonage-voice.md)\n- [SignalWire Voice API vs Voximplant](https://www.anchorterminal.com/compare/signalwire-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": "Bandwidth Voice API + MCP vs SignalWire Voice API", "url": "" } ], "description": "SignalWire Voice API has a score of 67.3 (B) against Bandwidth Voice API + MCP's 63.7 (B). Both do voice calls. The largest gap is transparency \u0026 trust, 15 points. Category scores, facts, verdicts and agent notes side by side.", "facts": [ "Bandwidth Voice API + MCP B 63.7", "SignalWire Voice API B 67.3", "scores" ], "h1": "Bandwidth Voice API + MCP vs SignalWire Voice API", "image": "https://www.anchorterminal.com/assets/og/compare-bandwidth-voice-vs-signalwire-voice.png", "path": "/compare/bandwidth-voice-vs-signalwire-voice", "published": "2026-10-01", "section": "tools", "title": "Bandwidth Voice API + MCP vs SignalWire Voice API for AI agents", "toc": null, "updated": "2026-10-04", "url": "https://www.anchorterminal.com/compare/bandwidth-voice-vs-signalwire-voice" }, "tokens": { "markdown": 1650, "slim": 330 }, "version": 1 }