# Introduction Start with BeliefState > Section: Overview > Last updated: **2026-09-09**. > API version: **v1 (Latest)**. OpenAPI publication: **2026-11-08**. ## Choose a starting point Pick the interface that matches your client and where its credentials can be kept safely. Use hosted MCP for an interactive AI. Use REST and OpenAPI for code that runs on your server. ### [Connect an agent](https://beliefstate.ai/connect) Connect a supported AI client, sign in, and prove one cited tool call. ### [Use the REST API](https://beliefstate.ai/docs/quickstart) Create a server side key and verify your first REST response. ### [Read the OpenAPI spec](https://beliefstate.ai/docs/openapi) Generate types or a client from the published machine readable contract. ### [Browse API reference](https://beliefstate.ai/docs/api/beliefs) Review released datasets and every supported request parameter. ## What you can access BeliefState exposes the intelligence record and the evidence needed to audit it. - Analyst beliefs, revisions, catalysts, risks, invalidations, and outcomes - Belief changes, event timelines, and consensus among tracked analysts - Thesis evidence, analyst comparisons, and comparable belief history - Research source profiles, coverage, access rights, and corpus eligibility ## Data contract Responses are structured JSON for machines first. Preserve the context fields alongside the result. ```text evidence + belief state + time + uncertainty + outcome ``` Keep citations, warnings, observation time, data mode, pagination, explicit unknowns, and methodology versions. They are part of the record, not display metadata. ## Next steps Choose the path that matches the system you are connecting. - [Connect a supported AI](https://beliefstate.ai/connect) - [Make your first REST request](https://beliefstate.ai/docs/quickstart) - [Review data provenance](https://beliefstate.ai/docs/provenance) ## Agent feedback Report unclear, stale, or incorrect documentation through [BeliefState support](https://beliefstate.ai/contact). Include this page URL and the smallest reproducible detail.