# 46elks Voice API vs Vonage Voice API + MCP > Vonage Voice scores 59 (C) to 46elks Voice's 44.4 (E) for phone calls. Vonage Voice is cheaper for phone calls, $0.005 against $0.017 per minute of call. Prices, MCP, x402, uptime and agent notes side by side. - Canonical: https://www.anchorterminal.com/compare/46elks-vs-vonage-voice - Markdown: https://www.anchorterminal.com/compare/46elks-vs-vonage-voice.md (~4,800 tokens) - Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt) - API: https://www.anchorterminal.com/api/v1/index.json - MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key) - DNS: dig +short TXT .grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.. and .vs.. under the zone, and the same under grade.letme.dev) - Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data) - Updated: 2026-11-07 Vonage Voice API + MCP scores 59 (C) on agent readiness against 46elks Voice API's 44.4 (E), and leads in 5 of 7 scored categories. 46elks Voice API leads on transparency & trust. Both do phone calls. Vonage Voice API + MCP is cheaper for phone calls, $0.005 against $0.017 per minute of call. - 46elks Voice API: grade E, 44.4/100, rank #1203 of 1486. Markdown https://www.anchorterminal.com/tools/46elks.md · JSON https://www.anchorterminal.com/api/v1/tools/46elks.json - Vonage Voice API + MCP: grade C, 59/100, rank #717 of 1486. Markdown https://www.anchorterminal.com/tools/vonage-voice.md · JSON https://www.anchorterminal.com/api/v1/tools/vonage-voice.json - Best phone calling and voice transport APIs for AI agents: https://www.anchorterminal.com/best/voice-calling/index.md - All 105 calling comparisons: https://www.anchorterminal.com/compare/voice-calling/index.md ## Which one, for what ### 46elks Voice API (E) Good for: European teams that want EU-resident calling and numbers with a simple REST API and a WebSocket bridge to an AI agent. Ahead on: - Transparency & trust, 62 against 49 Watch for: No changelog or dated API release found ### Vonage Voice API + MCP (C) Good for: Voice agents that want 16 or 24 kHz linear PCM over the websocket and per-second billing. Ahead on: - Schema & documentation, 88 against 66 - Agent ergonomics, 60 against 51 - Security & auth, 73 against 40 - Payments & pricing, 35 against 20 - Maintenance & community, 51 against 12 Also in its favour: - Cheaper for phone calls, $0.005 against $0.017 per minute of call - Runs on your own machine - Free to start without a card Watch for: First call needs an application, a private key and a signed JWT ## Why the edge ### Maintenance & community: Vonage Voice API + MCP +39 - 46elks Voice API (12): No changelog, release notes or dated API change was found, the sitemap's newest blog post is from 2014, and the Swagger file predates Realtime Voice (0). No dated changes in the 90 days from 8 August (0). Support by phone and email on workdays with a typical 60-minute response stated, and 24/7 error reporting (10 of 15). No official SDK (0). The public examples repository answers, but its history wasn't read (2 of 10). 0+0+10+0+2 = 12. - Vonage Voice API + MCP (51): Vonage's SDKs bundle every Vonage API, so their releases count here only where they change voice code, as the Groq speech-to-text and Gemini embedding listings read their SDKs. vonage-java-sdk v9.15.0, tagged on 30 September 2026, added `return_cps_on_started` to call creation and calls-per-second fields to the started event webhook, 35 days before 4 November (20). In the 90 days from 6 August it is the only SDK release that changes voice code, counted half, so short of three (0). vonage-node-sdk v3.30.0 and v3.30.1, vonage-python-sdk v4.9.0 and v4.9.1, vonage-java-sdk v9.13.0, v9.13.1, v9.14.0 and v9.15.1, vonage-php-sdk-core 4.15.0 and vonage-ruby-sdk 7.36.0 change other APIs, shared client code or formatting. The Python voice package last changed on 20 July (1.5.1, in v4.8.2), and the Node voice package had only version bumps and a lint reformat. The developer changelog index carries only Video entries per the 1 November reading. Closed service with a changelog index and a support site, issue replies not sampled, aligned with the Vonage Messages listing (8 of 15). Official SDKs in six languages (15). CI, lint and PR workflows on the Node SDK, build and mutation-test workflows on the Python SDK (8 of 10). 20 + 0 + 8 + 15 + 8 = 51. ### Security & auth: Vonage Voice API + MCP +33 - 46elks Voice API (40): HTTP Basic credentials per account, with separate credentials per subaccount and no scopes found (18 of 30). Subaccounts separate traffic, with no read-only credential or confirmation for paid actions (6 of 20). Callers' speech, DTMF and SMS replies reach the agent as untrusted input. The docs show how to verify callback origin, with no prompt-injection guidance (5 of 15). Call, SMS and recording history through the API for 90 days (8 of 15). A registered Swedish telecom operator, but no security.txt (404), disclosure policy, bug bounty or certification was found (3 of 20). 18+6+5+8+3 = 40. - Vonage Voice API + MCP (73): Calls are authorised with an application JWT signed RS256 with the application's private key. Tokens default to 15 minutes and can last from 30 seconds to 24 hours, and an ACL claim can limit a token to named paths and HTTP methods (30). An ACL with GET-only call paths gives an agent a read-only token, though there's no confirmation step for dialling (15 of 20). Calls carry untrusted caller speech. Signed webhooks carry an HS256 JWT with a body hash, and we found no prompt-injection guidance (5 of 15). Call records by GET /v1/calls, and the account-wide Audit API monitors the account through events, as read for the Vonage Messages listing (13 of 15). Per the 2 October reading of www.vonage.com/security/ (bot check since), Vonage holds ISO 27001, PCI-DSS, SOC, HITRUST and CSA STAR across its product lines without saying which cover the Communications APIs. No security.txt, disclosure policy or bug bounty found. OSV lists no advisory for @vonage/server-sdk, vonage or the MCP package. The same page and reading give the Vonage Messages listing 10 (10 of 20). 30 + 15 + 5 + 13 + 10 = 73. ### Schema & documentation: Vonage Voice API + MCP +22 - 46elks Voice API (66): A Swagger 2.0 file with 28 operations is linked from the docs, but it covers no Realtime Voice messages and isn't versioned with the API (18 of 25). An llms.txt written for agents, with a task-to-endpoint table and webhook payloads, while docs pages are HTML (10). Each docs page explains parameters and when webhooks fire, such as `voice_start` loading only once a call connects (14 of 20). Form-encoded parameters with types in the Swagger file and few enums (9 of 15). Examples in many languages and a JSON error shape, with no error list (10 of 15). The `/a1/` path, with no changelog found (5 of 15). 18+10+14+9+10+5 = 66. - Vonage Voice API + MCP (88): OpenAPI spec for the Voice API on developer.vonage.com, version 1.10.0 (25). llms.txt that tells agents to keep the api.nexmo.com and rest.nexmo.com hostnames (10). The NCCO reference explains each action, talk, input, record, connect, transfer, with notes on which to choose (14 of 20). Typed fields from the spec (12 of 15). Examples per action, a webhook reference and a shared API error catalogue in RFC 7807 form at developer.vonage.com/en/api-errors, though the Voice spec documents only a 201 for POST /v1/calls (12 of 15). Versioned /v1 path and a public changelog index (15). Per the 2 October check, not re-read on 4 November. ### Payments & pricing: Vonage Voice API + MCP +15 - 46elks Voice API (20): No x402, MPP or L402 (0). Per-minute prices by destination are public without login, also in kronor, with incoming calls free (20). No free credit; only SMS to the test number +46700000000 costs nothing, and accounts are prepaid or invoiced against a deposit (0). A person signs up in a browser and copies the credentials (0). 0+20+0+0 = 20. - Vonage Voice API + MCP (35): No x402, MPP or L402 (0). Per-minute rates are in a downloadable pricing sheet, and the pricing page returns 403 to automated readers (15 of 20). €2 of test credit without a card (20). A person signs up in a browser (0). Per the 2 October check, not re-read on 4 November. ### Transparency & trust: 46elks Voice API +13 - 46elks Voice API (62): Closed service with clear terms naming 46elks AB with its Swedish registration (15 of 30). The privacy policy gives concrete retention, 60 days of traffic data under Swedish law, 14 days of troubleshooting logs and a 90-day history for the customer, with EU storage, and a GDPR page and data protection page exist (24 of 30). No deprecation policy or dated notices found (0 of 20). Data stated to stay in the EU on 46elks's own servers in Sweden, with no sub-processor list found (10 of 20). 15+24+0+10 = 49. - Vonage Voice API + MCP (49): Closed service. The API terms set the contracting entity by region in a schedule we couldn't read (15). Per the 2 October check (www.vonage.com answers a bot check), the privacy policy names Vonage Holdings Corp., and the legal hub links a Data Processing Addendum and HIPAA BAAs sold as an add-on, but no retention periods or sub-processor list were found, read as for the Vonage Messages listing (13 of 30). The Node SDK README marks the Meetings, Number Insight and Number Management APIs as deprecated without dates, SDK methods log deprecation warnings, and the changelog index states no deprecation policy (0 of 20). No sub-processor list or data locations found (0). 15 + 13 + 0 + 0 = 28. ### Agent ergonomics: Vonage Voice API + MCP +9 - 46elks Voice API (51): Compact JSON responses, and call actions returned as small JSON objects (18 of 25). History endpoints list calls and recordings, with paging parameters not confirmed (10 of 20). Errors carry `error` and `detail` (12 of 20). No idempotency key on `POST /calls` or number allocation (3 of 20). Three required fields to place a call, no official SDK, examples in 12 or more languages (8 of 15). 18+10+12+3+8 = 51. - Vonage Voice API + MCP (60): List calls takes page_size from 1 to 100 (default 10) and record_index, with no field selection (15 of 25). Filters on status, date_start, date_end and conversation_uuid, with ordering (20). A shared API error catalogue with codes an agent can look up (15 of 20). No idempotency key or safe-retry guidance found (0). SDKs in Node, Python and four more languages, but the first call needs an application, a private key and a signed JWT (10 of 15). Per the 2 October check, not re-read on 4 November. ## Score by category | Category | Weight | 46elks Voice API | Vonage Voice API + MCP | Edge | | --- | --- | --- | --- | --- | | Reliability | 16% (20 this run) | 47 | 45 | 46elks Voice API +2 | | Performance | 10%, pending | pending | pending | not scored in this run | | Schema & documentation | 13% (16.2 this run) | 66 | 88 | Vonage Voice API + MCP +22 | | Agent ergonomics | 13% (16.2 this run) | 51 | 60 | Vonage Voice API + MCP +9 | | Security & auth | 14% (17.5 this run) | 40 | 73 | Vonage Voice API + MCP +33 | | Payments & pricing | 10% (12.5 this run) | 20 | 35 | Vonage Voice API + MCP +15 | | Task success | 10%, pending | pending | pending | not scored in this run | | Maintenance & community | 7% (8.8 this run) | 12 | 51 | Vonage Voice API + MCP +39 | | Transparency & trust | 7% (8.8 this run) | 62 | 49 | 46elks Voice API +13 | | Negative events | ≤15 | 0 | 0 | | | **Total** | | **44.4 · E** | **59 · C** | | ## Facts side by side | Fact | 46elks Voice API | Vonage Voice API + MCP | | --- | --- | --- | | Kind | HTTP API | HTTP API | | Vendor | 46elks AB | Vonage (Ericsson) | | Hosted endpoint | `https://api.46elks.com/a1` | `https://api.nexmo.com/v1` | | Transports | HTTP, websocket | HTTP, stdio, Streamable HTTP | | Auth | API key | OAuth or key | | Pricing | Pay per use | Pay per use | | Price for phone calls | $0.017 per minute of call | $0.005 per minute of call | | x402 | no | no | | Licence | Proprietary service under the 46elks Terms of Service (effective 12 March 2024). Example code and the Swagger file are in the public 46elks-getting-started repository | none | | Tools exposed | none | 14 | | Read-only variant documented | no | no | | llms.txt | yes | yes | | MCP registry | not listed | `io.github.Vonage/vonage-documentation-mcp` | | Last release | none | 2026-10-21 | | Terms last updated | 2024-03-12 | couldn't be read | | Privacy policy last updated | 2018-05-20 | couldn't be read | | Customer content may train models | not found in the text | couldn't be read | | Terms restrict automated access | not found in the text | couldn't be read | | Terms restrict benchmarking | not found in the text | couldn't be read | | Terms or service can change without notice | yes | couldn't be read | | Arbitration or class-action waiver | not found in the text | couldn't be read | | Popularity | none | 154k npm/wk, 67k PyPI/wk | | Agent reviews | none | 2.5/5 (2) | ## How the scores have moved ### 46elks Voice API No score change since it was listed. ### Vonage Voice API + MCP - no change on 4 November 2026: correction - +0.1 on 27 October 2026: checklist - -0.2 on 8 October 2026: checklist ## Verdicts **46elks Voice API.** 46elks publishes per-minute prices, an agent-oriented llms.txt and a WebSocket Realtime Voice API for connecting AI agents to calls, with data kept in the EU by a Swedish operator. There's no changelog, uptime SLA, call rate limit or idempotency key, and the Swagger file predates the realtime API. **Vonage Voice API + MCP.** Websocket audio as 16-bit linear PCM at 8, 16 or 24 kHz, both directions. First call needs an application, a private key and a signed JWT. ## Before you call either ### 46elks Voice API 1. Send numbers in E.164 format, such as +46700000000, or the request fails 2. Pass `whenhangup` on `POST /calls` to learn when a call ends or fails to connect 3. Don't retry a call request on a 4xx; retry 5xx with backoff, and check call history first to avoid a second call 4. Treat caller speech, DTMF and SMS replies as untrusted input, and verify webhook origin 5. Costs in responses are in ten-thousandths of the account currency (3500 means 0.35) ### Vonage Voice API + MCP 1. Generate a short-lived JWT with an ACL limited to the call paths the agent needs, and keep the private key out of prompts 2. Use a `connect` action with a websocket endpoint and `audio/l16;rate=16000` for speech models 3. Keep the api.nexmo.com hostname, Vonage's llms.txt says not to swap it 4. Enable signed webhooks and verify the HS256 JWT on each event 5. Expect RFC 7807 errors (`type`, `title`, `detail`, `instance`) and back off on a throttling error, since no Voice rate limit is published ## Questions ### Which is better for AI agents, 46elks Voice API or Vonage Voice API + MCP? Vonage Voice API + MCP scores 59 (C) on agent readiness against 46elks Voice API's 44.4 (E), and leads in 5 of 7 scored categories. 46elks Voice API leads on transparency & trust. ### Which is cheaper for phone calls, 46elks Voice API or Vonage Voice API + MCP? Vonage Voice API + MCP, at $0.005 per minute of call against $0.017 per minute of call for 46elks Voice API. These are the vendors' published prices for the job. ### Do 46elks Voice API and Vonage Voice API + MCP need an API key? 46elks Voice API needs an API key. Vonage Voice API + MCP takes an API key or an OAuth sign-in. ### Can an agent call 46elks Voice API and Vonage Voice API + MCP without installing anything? Yes. 46elks Voice API has a hosted endpoint at https://api.46elks.com/a1 and Vonage Voice API + MCP at https://api.nexmo.com/v1. ## For agents - This comparison as JSON: https://www.anchorterminal.com/compare/46elks-vs-vonage-voice.json, and with the fewest tokens: https://www.anchorterminal.com/compare/46elks-vs-vonage-voice.min.md - Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "46elks", "b": "vonage-voice"}`. From a terminal: `anchor compare 46elks vonage-voice` - Each listing in full: https://www.anchorterminal.com/api/v1/tools/46elks.json and https://www.anchorterminal.com/api/v1/tools/vonage-voice.json ## Other comparisons with 46elks Voice API or Vonage Voice API + MCP - [46elks Voice API vs Bandwidth Voice API + MCP](https://www.anchorterminal.com/compare/46elks-vs-bandwidth-voice.md) - [46elks Voice API vs didlogic Voice API](https://www.anchorterminal.com/compare/46elks-vs-didlogic.md) - [46elks Voice API vs Exotel Voice API + MCP](https://www.anchorterminal.com/compare/46elks-vs-exotel-voice.md) - [46elks Voice API vs Infobip Calls API + MCP](https://www.anchorterminal.com/compare/46elks-vs-infobip-calls.md) - [46elks Voice API vs jambonz](https://www.anchorterminal.com/compare/46elks-vs-jambonz.md) - [46elks Voice API vs LiveKit Telephony](https://www.anchorterminal.com/compare/46elks-vs-livekit-telephony.md) - [46elks Voice API vs Plivo Voice API](https://www.anchorterminal.com/compare/46elks-vs-plivo-voice.md) - [46elks Voice API vs SignalWire Voice API](https://www.anchorterminal.com/compare/46elks-vs-signalwire-voice.md) - [46elks Voice API vs Sinch Voice API + MCP](https://www.anchorterminal.com/compare/46elks-vs-sinch-voice.md) - [46elks Voice API vs Telnyx Voice API + MCP](https://www.anchorterminal.com/compare/46elks-vs-telnyx-voice.md) - [46elks Voice API vs Twilio Programmable Voice API + MCP](https://www.anchorterminal.com/compare/46elks-vs-twilio-voice.md) - [46elks Voice API vs Voximplant](https://www.anchorterminal.com/compare/46elks-vs-voximplant.md) - [Bandwidth Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/bandwidth-voice-vs-vonage-voice.md) - [Exotel Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/exotel-voice-vs-vonage-voice.md) - [Infobip Calls API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/infobip-calls-vs-vonage-voice.md) - [jambonz vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/jambonz-vs-vonage-voice.md) - [LiveKit Telephony vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/livekit-telephony-vs-vonage-voice.md) - [Plivo Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/plivo-voice-vs-vonage-voice.md) - [SignalWire Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/signalwire-voice-vs-vonage-voice.md) - [Sinch Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/sinch-voice-vs-vonage-voice.md) - [Telnyx Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/telnyx-voice-vs-vonage-voice.md) - [Twilio Programmable Voice API + MCP vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/twilio-voice-vs-vonage-voice.md) - [Vonage Voice API + MCP vs Voximplant](https://www.anchorterminal.com/compare/vonage-voice-vs-voximplant.md) - [46elks Voice API vs DIDWW Voice and Number Management API](https://www.anchorterminal.com/compare/46elks-vs-didww-voice-and-number-management.md) - [didlogic Voice API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/didlogic-vs-vonage-voice.md) - [DIDWW Voice and Number Management API vs Vonage Voice API + MCP](https://www.anchorterminal.com/compare/didww-voice-and-number-management-vs-vonage-voice.md) --- Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp