Start with one free API call
No registration, wallet, card or signing key is needed for a first direct request. Choose a task, send HTTP and inspect the result. Credentials and delegated orders are optional for individual quotas and recurring workflows.
1. Try the smallest working example
curl 'https://agentutility.network/api/v1/tools' \
-H 'Content-Type: application/json' \
--data '{"tool":"content-hash","input":"abc"}'Expect algorithm SHA-256, utf8_bytes 3, and hash ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad. One admitted call consumes one quota unit. For text operations you can compute locally too; AUN is useful when a workflow needs one consistent hosted API.
2. Choose the right task
| Need | Call | Guide |
|---|---|---|
| Bibliographic metadata for a DOI | GET /api/v1/doi?doi=... | DOI |
| Public DNS records | GET /api/v1/dns?domain=... | DNS snapshot |
| JSON syntax, SHA-256 or text counts | POST /api/v1/tools | Utilities |
| DOI/title consistency for 1–5 citations | POST /api/v1/bibliography | Citation checks and quality evidence |
Do not use AUN to certify scientific truth, website safety, domain availability or semantic correctness. DNS and bibliographic data go to the documented providers. Text utilities run on AUN's backend. Inspect per-item status and limitations; HTTP 200 does not guarantee every item succeeded.
3. Handle quotas and errors
GET /api/v1/usage reads the shared anonymous allowance without consuming usage units. Anonymous callers share 100 units per UTC day; own credentials have 1,000 units per UTC month inside the global 10,000-unit monthly ceiling. DNS costs five, bibliography one per citation, other admitted utility/metadata calls one. Admitted failures consume units. Rate and antiabuse limits apply separately.
Errors have {"error":"human explanation","code":"machine_class"}. On 429, respect Retry-After. quota_exhausted also provides reset_at; rate_limited is a request/concurrency throttle. Invalid credentials return 401; never silently fall back to anonymous mode. Do not rapidly retry provider errors or automatically repeat failed orders. Data, privacy and limits.
4. Add a credential only when needed
Automatic Ed25519 enrollment proves possession of your signing identity and returns an expiring root token once. Keep it private and delegate only needed services, scopes and units to an executing agent. This is not human verification or financial spending authority. The full quote/order/receipt flow is optional; direct calls remain the shortest path. No paid checkout or financial mandate exists.
MCP for compatible hosts
Remote stateless Streamable HTTP endpoint: https://api.agentutility.network/mcp. Default authentication is none; some hosts can optionally attach an AUN Bearer token. No OAuth server is advertised. The SDK supports current per-request discovery and legacy stateless clients; compatibility is verified with the official client, not every host.
{"mcpServers":{"aun":{"url":"https://api.agentutility.network/mcp"}}}This is a common configuration shape; the exact setting name depends on your host. Add the remote URL in hosts that support Streamable HTTP. Available tools: lookup_doi, lookup_dns, run_utility, check_bibliography and get_usage. All reuse the HTTP quotas and service scopes. There are no shell, credential-issuance, payment or server-administration tools. Native MCP clients should omit Origin; browser MCP requests are limited to AUN origins. Browser applications on other origins can use the public REST API instead.
Dependency-free CLI
Download aun-cli.mjs and run it with Node.js 24:
node aun-cli.mjs help node aun-cli.mjs catalog printf 'abc' | node aun-cli.mjs hash node aun-cli.mjs dns example.com
Pass private text via stdin or --file PATH, not inline shell arguments. Set an optional AUN_API_KEY in your own environment; it is sent only to the official domain. There are no automatic retries or payments. The CLI is downloadable source, not a package claimed to be published on npm.
Browser applications
REST endpoints support CORS for GET/POST with Content-Type and an explicitly supplied Authorization header. Cookies and credentialed CORS are not supported. CORS does not bypass authentication, service scopes, quotas or antiabuse.
Versioning and compatibility
Canonical REST routes use /api/v1. Original /api routes remain aliases. Responses include AUN-API-Version: 1 and a service-desc Link header. Additive fields can appear in v1; breaking request/response changes require a new major route and migration instructions. No v1 retirement is scheduled. A planned retirement will be announced at least 90 days ahead. Bibliography method.version is 2 and title_similarity is informational; use title_check. Prior diagnostic sources/results remain available for comparison.
Machine entry points
Complete OpenAPI 3.1 · RFC 9727 API catalog · Service overview · MCP endpoint description · When-to-use guidance. These documents aid compatible clients; they do not guarantee search ranking or discovery.