Quickstart
Create a key, check your balance and run your first search.
Authentication
Keys, scopes and daily spending caps.
Pricing and billing
What each call costs, and how a call is charged.
API reference
Every endpoint, with a playground.
Base URL
/v1, the API’s version. The API is served only over HTTPS.
What you can do
Conventions
- Requests and answers are JSON over HTTPS. Send
Content-Type: application/jsonwith a body. - Money is in US dollars, written as an exact six-decimal string such as
"0.000500", never as a float. - Timestamps are ISO 8601 in UTC, such as
"2026-11-14T10:02:11.000Z". - Ids are opaque strings. Never parse or build them.
- Every answer carries an
X-Request-Idheader, the money headersX-Charged-UsdandX-Balance-Usd, and the rate-limit headers. See Pricing and billing and Rate limits. - Errors always use one envelope with a stable
code. See Errors.
Building with an agent?
Point it at docs.outbound.dev/llms.txt: these docs in plain text, for the agent to read before it calls. The OpenAPI document behind the API reference is at api.outbound.dev/v1/openapi.json.Need help?
Write to hello@outbound.dev and include theX-Request-Id of the call: it lets us find the exact request.