# API versioning Understand current and future API contract boundaries > Section: Overview > Last updated: **2026-09-09**. > API version: **v1 (Latest)**. OpenAPI publication: **2026-11-08**. ## Current version Use the v1 route prefix for every released REST operation. The visible Latest tag identifies the current documentation set. | Contract | Value | Meaning | | --- | --- | --- | | REST route | `/v1` | Latest supported major version | | OpenAPI publication | `2026-11-08` | Current generated contract publication | | Historical docs | None | No earlier public snapshot is presented | - [Download the current OpenAPI contract](https://beliefstate.ai/openapi.json) - [Review API changes](https://beliefstate.ai/docs/changelog) ## Read version fields Route, OpenAPI, and payload versions answer different compatibility questions. Keep all three with stored research responses. | Field | Scope | | --- | --- | | `/v1` | Major REST request and response contract | | `info.version` | Publication of the generated OpenAPI document | | `schema_version` | Schema carried by a specific response record | ## Major version boundary The current documentation has no earlier public major version snapshot, so the navigation shows the current version without an empty selector. - The September 9 consolidation keeps /v1, retires overlapping routes and tools, and adds belief_id and source search filters to the remaining resources. Update saved requests and refresh tool discovery using the changelog. - Future major payload contracts use a new route prefix. The version selector lists only documentation backed by a separate, published snapshot. - A historical option never aliases current documentation or implies support that does not exist. ## Endpoint lifecycle A deprecated operation publishes its announcement, optional removal date, replacement, and migration steps on the endpoint page. > Preview and Deprecated labels describe one operation's lifecycle. They do not create a new major API version. - [Review the API reference](https://beliefstate.ai/docs/api/beliefs) - [Review the changelog](https://beliefstate.ai/docs/changelog) ## Agent feedback Report unclear, stale, or incorrect documentation through [BeliefState support](https://beliefstate.ai/contact). Include this page URL and the smallest reproducible detail.