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The Krun API is a JSON-over-HTTPS API.

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Endpoints

All /v1 endpoints require an API key. See Authentication. The API also serves GET /health for liveness checks and GET /openapi.json, both without authentication.

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OpenAPI specification

The API reference pages are generated from the live OpenAPI 3.1 specification:
Use it to generate clients or import the API into tools like Postman. Each endpoint page has an interactive playground: add your API key under Authorization to send real requests.
Playground requests are real API calls: they use your quota and are sent through the documentation site’s proxy. Use a key you can rotate, and never paste a key on a shared screen.

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Request ids

Every response has an X-Request-ID header. Successful /v1/decide responses don’t repeat it in the body, and error bodies include it as error.request_id. You can send your own X-Request-ID with a request: 1 to 128 characters of letters, digits, ., _, : and -. Krun keeps it and returns it. Otherwise it generates one like req_0cf5441281f640ffbf0111c5a3ed9e50. Use the request id to send feedback and when you contact support.

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Conventions

  • Request and response bodies are JSON. Send Content-Type: application/json.
  • Field names are snake_case. Your question ids and option ids are returned exactly as sent.
  • Unknown fields in a request are rejected with 400 INVALID_REQUEST.
  • Request bodies are limited to 256 KiB.
  • Errors share one format. See Errors.

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Versioning

The major version is part of the path (/v1). Changes that could break existing clients will ship under a new version. New optional fields can be added to /v1 responses, so ignore fields you don’t recognize. The current specification version is 1.0.0-beta: the API is in closed beta.