5. Release it

A release is an immutable, SemVer-tagged revision of main. Serving endpoints, MCP servers, exports and the assistant all read releases, so consumers only see what you have reviewed.

Merge the change request

Open Change requests › #n (/models/:id/change-requests/:n). The checks run when the request opens and again on Re-run checks:

Check	Blocks the merge?
Validation — names, unknown entities and columns, join keys, ambiguous join paths, non-additive sums, unresolved or cyclic metric references, time metrics without a time dimension. Fan and chasm traps are warnings.	Yes, on errors
Breaking changes — objects in the latest release that the request removes or redefines, with their consumers (serving query log of the last 30 days, exports).	Yes, until acknowledged
Data quality — failing rules behind changed metrics.	No (warning)
Governance — changes to certified metrics need an approval from someone who can govern.	Yes

Then:

1. Approve (:review). The required number of approvals is a model setting (default 1). An author can't approve their own request unless they can govern.
2. Merge (:merge). It is a three-way merge per object. If a branch moved since the checks ran, the merge answers 409 Modeling.ChecksOutdated: re-run the checks. Two concurrent merges can't both win (409 Modeling.BranchMoved).
3. Publish release (POST …/models/{id}/releases). Keel suggests the version from the diff: removed or redefined metrics, dimensions or measures → major; additions → minor; documentation only → patch. Add notes.

After the release

• Lineage is rebuilt, glossary term suggestions refresh, and the default access-policy suggestion is proposed.
• A rollback publishes an earlier release's revision as a new release (:rollback).
• A release always compiles the same query to byte-identical SQL.

Serve it

• Semantic query API — publish a serving endpoint and query it with an API key.
• MCP for AI agents — the same endpoint as an MCP server.
• Exports — dbt, Cube, LookML, Power BI (TMDL), open YAML.