# DIDWW Voice and Number Management API (slim)

> DIDWW is a telecoms carrier selling phone numbers in more than 90 countries with inbound and outbound SIP trunking. Its REST API v3 orders numbers and configures trunks and capacity, and a remote MCP server covers the same account tasks.

- Full: https://www.anchorterminal.com/tools/didww-voice-and-number-management.md (~9,050 tokens) · this version ~1,880 tokens · JSON https://www.anchorterminal.com/tools/didww-voice-and-number-management.json · canonical https://www.anchorterminal.com/tools/didww-voice-and-number-management
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · Updated: 2026-10-10

**B · 65.1/100 · rank #330 of 950 · #5 in Phone calling & voice transport · not agent-ready · confidence medium**


Assessment: 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.

## Facts

- Kind: HTTP API · vendor: DIDWW Ireland Limited · category: Phone calling & voice transport · legal entity: DIDWW Ireland Limited · provenance 85/100
- Endpoint: `https://api.didww.com/mcp` (HTTP)
- Auth: API key · pricing: Pay per use · x402: no · licence: Proprietary service under the DIDWW Terms and Agreements (Rev 3.1). The OpenAPI repository and the official SDKs are MIT
- Probe metrics: not measured yet (probes haven't run)
- Countries with numbers: More than 90 countries by the vendor's count (one llms.txt line says more than 100). Local, national, mobile, toll-free, shared-cost and UIFN numbers. Many countries need a verified identity and address first
- SIP: Inbound SIP trunks with trunk groups for failover and load balancing, PSTN forwarding trunks, and outbound trunks over UDP, TCP or TLS with optional encrypted media. Points of presence in New York, Los Angeles, Miami, Frankfurt, Amsterdam, Singapore and Hong Kong
- Call control: None in the API. Calls are placed by a SIP INVITE from the customer's system and received on the customer's SIP endpoint. The API orders numbers and configures trunks, capacity and compliance records
- Media streams: None found. No websocket or media fork is documented for API v3
- Recording: None found for API v3. Recording belongs to phone.systems, a separate cloud PBX product
- Call events: Webhooks for inbound and outbound call start, connect and end, and CDR streaming. Enabled by Technical Support on request, then configured in the User Panel
- Outbound calling: Not enabled at sign-up. An application form is reviewed, and it needs a business account with a company name and VAT or tax ID. Local termination needs a number in the account
- Free tier: Sandbox with its own account and keys, no real provisioning or billing, funded by Stripe test cards. Production needs a $30 prepaid balance
- Rate limits: 20 requests a second per API key, with `429` over the limit. MCP requests are counted per connected client and a refusal gives the seconds to wait
- SLA: None found. The terms give no warranty that the service is continuous or free from faults
- Data retention: No retention periods in the Privacy Notice. DID history covers 90 days and finished export files are kept one month. The notice names the USA, Singapore and Germany among processing countries
- MCP server: `https://api.didww.com/mcp`, Streamable HTTP with OAuth, 82 tools in the docs. Guides for Claude, ChatGPT and Perplexity. The vendor says it is for account tasks and does not replace the API for software integrations

- Scores: Reliability 66, Performance pending, Schema & documentation 87, Agent ergonomics 77, Security & auth 57, Payments & pricing 15, Task success pending, Maintenance & community 83, Transparency & trust 70 · total over the 7 assessed categories
- Why: Reliability, Graded as a hosted service on the REST API v3. A public status page on Instatus lists eight components, among them DIDWW API, Inbound Voice… · Schema & documentation, A public OpenAPI 3.0.3 document for version 2026-04-16 describes 107 operations on 67 paths with 242 schemas, in JSON and YAML, with a disco… · Agent ergonomics, Sparse fieldsets with `fields[...]`, `include` for related resources and `page[size]` let a caller size replies. · Security & auth, REST API keys are named, revocable and can be limited to source IP addresses. · Payments & pricing, No x402, MPP or L402 found (0). · Maintenance & community, The public OpenAPI document was last revised on 6 October 2026 and the Ruby, Python and TypeScript SDKs were tagged on 7 October 2026 (30). · Transparency & trust, The service is closed, under the DIDWW Terms and Agreements, Rev 3.1, with a named Irish legal entity.
- Sources: 43, open questions: 12, both in the full twin
- Capabilities: voice.numbers, voice.sip
- JSON: https://www.anchorterminal.com/api/v1/tools/didww-voice-and-number-management.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/didww-voice-and-number-management.svg` or a link to https://www.anchorterminal.com/tools/didww-voice-and-number-management from a page on didww.com or one of its subdomains, or the README of github.com/didww/didww-api-3-openapi, 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 `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`

## Connect

```bash
npm install @didww/sdk
```

```bash
GET https://api.didww.com/v3/countries
Api-Key: YOUR_API_KEY
X-DIDWW-API-Version: 2026-04-16
Accept: application/vnd.api+json
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/didww-voice-and-number-management

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