# jambonz (slim)

> jambonz is a programmable voice platform from FirstFive8 for calls over a customer's own SIP carriers. Applications control calls through a REST API, webhooks or a WebSocket API, on the hosted jambonz.cloud or a self-hosted cluster under a commercial licence.

- Full: https://www.anchorterminal.com/tools/jambonz.md (~8,400 tokens) · this version ~1,930 tokens · JSON https://www.anchorterminal.com/tools/jambonz.json · canonical https://www.anchorterminal.com/tools/jambonz
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-09

**D · 49.2/100 · rank #712 of 842 · #11 in Phone calling & voice transport · not agent-ready · confidence medium**


Assessment: OpenAPI 3.1 and AsyncAPI documents, an llms.txt and Markdown pages cover the REST and WebSocket APIs, and session prices are public. No status page, security.txt or advisory was found, API keys carry no scopes, and the 2021 privacy policy says audio is never stored while the October 2026 release notes say support keeps call audio for a few days.

## Facts

- Kind: HTTP API · vendor: FirstFive8, Inc. · category: Phone calling & voice transport · legal entity: FirstFive8, Inc. · provenance 57/100
- Local only (HTTP): npm `@jambonz/sdk`, pypi `jambonz-python-sdk`, npm `@jambonz/mcp-schema-server`
- Auth: API key · pricing: Paid · x402: no · licence: Proprietary. jambonz.cloud is under the jambonz Terms of Use and self-hosted jambonz Commercial needs a paid licence key. The API server, feature server and SDK repositories on GitHub are MIT
- Probe metrics: not measured yet (probes haven't run)
- Countries with numbers: None sold. Numbers come from the customer's own SIP carrier and are registered in jambonz through the portal or `/PhoneNumbers`
- SIP: Carrier trunks with IP allow lists or registration, SIP clients, least cost routing, SIP REFER, SIPREC, TLS and SRTP. The release notes say jambonz.cloud keeps plain RTP to TLS-registered devices for now
- Media streams: The `listen` and `stream` verbs fork call audio to a websocket, with dual streams and per-member conference forks. A WebRTC SDK covers browsers and React Native
- Voice AI layer: `agent` and `llm` verbs with the customer's own keys for 14 LLM providers and for speech vendors. Model and speech charges are billed by those vendors
- Recording: SIPREC to an outside server, or recording uploaded to the customer's S3, Azure or Google Cloud bucket, started, paused and stopped by verb or `PUT /Accounts/{AccountSid}/Calls/{CallSid}`
- Transfer: `transfer` verb since 11.0.0 (8 July 2026) for blind transfer by SIP REFER or bridged dial and warm transfer by hold or three-way conference
- Free tier: Three-week trial on jambonz.cloud (the terms say 21 days). Self-hosted trial licence of 30 days and 10 concurrent sessions, one per domain, non-production
- Rate limits: The docs page gives 600 requests per 5 minute fixed window per client IP address. The 11.1.6 notes give 4,000 call creations and 600 call status reads a minute per account
- SLA: No uptime SLA found for jambonz.cloud. Support SLAs are sold with the Enterprise support plan for self-hosted systems, priced by quote
- Data retention: Usage data 30 days per the privacy policy. Call detail records can be switched off. Support keeps SIP and RTP from calls for a few days unless the account opts out (11.1.6)
- Self-hosting: Debian packages, AWS, Azure, GCP and OCI images and Kubernetes. A licence key tied to the domain is required and the instance reports hourly call counts to FirstFive8
- MCP server: Docs and schema only. `https://docs.jambonz.org/_mcp/server` and `@jambonz/mcp-schema-server` (two tools, hosted at `https://mcp-server.jambonz.app/mcp`). No MCP server for call control was found
- Prices: Cloud, concurrent session (5 to 249 sessions) $8 per month (plan); Cloud, concurrent session (250 to 499 sessions) $6 per month (plan); Cloud, concurrent session (500 or more sessions) $5 per month (plan); Self-hosted licence, concurrent session $7 per month (plan); Self-hosted licence, unlimited sessions $2000 per month (plan); Installation support package $1000 per transaction

- Scores: Reliability 36, Performance pending, Schema & documentation 78, Agent ergonomics 54, Security & auth 42, Payments & pricing 40, Task success pending, Maintenance & community 78, Transparency & trust 50 · negative events -3 · total over the 7 assessed categories
- Why: Reliability, Graded as a hosted service, the API on jambonz.cloud, which the docs name as the simplest way to start. · Schema & documentation, Three OpenAPI 3.1 documents are public (REST Call Control with 10 operations, REST Platform Management with 116, Webhooks with 4), with an A… · Agent ergonomics, Live calls can be filtered by direction, number and status, with no field selection or limit (13 of 25). · Security & auth, Bearer API tokens belong to an account or a service provider and carry `expires_at` and `last_used` fields. · Payments & pricing, Scored on the hosted option, jambonz.cloud. · Maintenance & community, jambonz Commercial 11.1.6 is dated 4 October 2026 and jambonz-api-server was tagged v0.9.15 on 7 October (30). · Transparency & trust, The API server, feature server and SDKs are public under MIT.
- Sources: 31, open questions: 11, both in the full twin
- Capabilities: voice.calls, voice.sip, voice.streaming, voice.recording, voice.agent
- JSON: https://www.anchorterminal.com/api/v1/tools/jambonz.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/jambonz.svg` or a link to https://www.anchorterminal.com/tools/jambonz from a page on jambonz.org or one of its subdomains, or the README of github.com/jambonz/jambonz-feature-server, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.

## Before you call it

1. Send `Authorization: Bearer <token>` to `https://api.jambonz.cloud/v1`, the server in the OpenAPI files. The REST introduction page gives `https://jambonz.cloud/api` instead, so confirm the base URL with the operator
2. Create a call with `from`, `to` and either `application_sid` or `call_hook`. Do not retry a timed-out create without checking `GET /Accounts/{AccountSid}/Calls` first
3. Read `ratelimit-remaining` and `ratelimit-reset` on every response and stop when a `429` arrives
4. Append `#rc=3&rp=5xx,ct` to an application URL to turn on webhook retries. HTTP webhooks are not retried by default
5. Check the account has a carrier and speech credentials before dialling. jambonz does not supply numbers, minutes or speech services

## Connect

```bash
npm install @jambonz/sdk
```

```bash
POST https://api.jambonz.cloud/v1/Accounts/{AccountSid}/Calls
Authorization: Bearer <token>
Content-Type: application/json
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/jambonz

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| --- | --- | --- | --- | --- |
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| Telnyx Voice API + MCP | BB | 74.2 | voice.calls, voice.streaming, voice.sip, voice.recording | https://www.anchorterminal.com/tools/telnyx-voice.min.md |
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| Bandwidth Voice API + MCP | B | 63.7 | voice.calls, voice.streaming, voice.sip, voice.recording | https://www.anchorterminal.com/tools/bandwidth-voice.min.md |
| Sinch Voice API + MCP | B | 62.7 | voice.calls, voice.streaming, voice.sip, voice.recording | https://www.anchorterminal.com/tools/sinch-voice.min.md |


## Panel reviews (0, desk reviews from public material, no calls made)