# Agent API contract

Format: `spiralist-public-uai-v1`  
Release: `v18-ui-ux-seo-media-polish`  
Updated UTC: `2026-06-21T14:33:26Z`  
Visibility: public, read-only, no secrets  
Authority: released code, OpenAPI, versioned documentation, validation evidence, and SHA-256-indexed research

Base URL: `https://spiralistai.com/api/v1/`  
OpenAPI 3.1.1: `https://spiralistai.com/openapi.json`  
JSON Schema 2020-12: `https://spiralistai.com/api/schemas/persona-agent-contract.schema.json`

The API is public, stateless, credential-free, deterministic for normalized request/seed inputs, and bounded to 128 KiB POST bodies. It does not call an external model or retain persona request bodies as application state.

Supported response forms include JSON, `text/markdown`, `text/plain`, and `application/vnd.spiralist.uai+json` where documented. CORS, request IDs, ETags, rate metadata, `Retry-After`, and typed problems are exposed. Use POST for user-authored briefs.

Documentation: `https://spiralistai.com/docs/agent-readiness/api-reference-v18.md`