DIDWW Voice and Number Management API vs jambonz

DIDWW Voice and Number Management API

An OpenAPI 3.0.3 document with 107 operations, Markdown docs, a free sandbox and SDKs in seven languages cover number ordering and SIP trunk set-up. No per-number or per-minute price is public, API keys carry no scopes, orders have no idempotency key, and outbound calling needs an approved application. Calls travel over SIP only.

jambonz

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.

DIDWW Voice and Number Management API

1. Send Api-Key: <key> with no Bearer prefix, plus Accept: application/vnd.api+json, and Content-Type: application/vnd.api+json on every request with a body
2. Set X-DIDWW-API-Version: 2026-04-16 on each request and read meta.api_version in the reply. A header older than the account's version is ignored
3. Before retrying a timed-out POST /orders, list GET /orders first. The order is charged to the balance at once and no idempotency key exists
4. Stay under 20 requests a second per key. On 429 wait before retrying, since no Retry-After header is documented
5. Use fields[...], filter[...], include and page[size] (default 50, maximum 100) to keep JSON:API replies small
6. Check GET /address_requirements before buying a number. Many countries need a verified identity and address, and the sandbox cannot run identity verification
7. Create and enable a callback secret in the User Panel before relying on callbacks. Without one nothing is sent, and receivers must verify X-DIDWW-Signature

jambonz

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