Releases

Releases are automated by release-please in .github/workflows/publish.yml. Every push to main re-computes the next version from the conventional commit messages and keeps a single release PR open, titled chore(main): release X.Y.Z and labelled autorelease: pending.

Merging that PR is what releases. It tags vX.Y.Z, creates the GitHub release, publishes to npm, and dispatches a version update to the agent registry.

There is no manual release button, and versions are never typed in by hand: the version is an output of the commit history, not an input.

Every other push to main publishes a preview instead — see Preview releases. Anything merged to main is on npm within minutes; there is no staging branch.

Releasing

npm run release:preflight

This reports the open release PR, the version it will ship, and checks that the repository is in a state where merging is safe. Nothing has to be remembered — if it exits non-zero, follow what it prints instead of merging.

Then merge it, using the PR number the preflight printed:

gh pr merge <pr-number> --squash
gh run watch "$(gh run list --workflow=publish.yml --limit 1 --json databaseId --jq '.[0].databaseId')"

The run is looked up rather than picked interactively, so this is safe to script. If the workflow has already finished, gh run list --workflow=publish.yml shows the outcome instead.

Merging main requires no review, so a green preflight and Build are the only gates. Once the workflow finishes, confirm both outputs landed:

gh release view "v<version>"
npm view "@agentclientprotocol/claude-agent-acp@<version>"

Preview releases

Every push to main that is not a release merge publishes a preview from the same workflow. There is no GitHub release — only an npm publish under the preview dist-tag, a v<version> tag on the commit it came from, and the same agent registry update a stable release dispatches, since the registry has its own handling for preview versions.

Those are three jobs, in that order: publish-npm-preview mirrors publish-npm and does nothing but publish; publish-tag-preview creates the tag; and trigger-registry-update is shared with the stable path. Before dispatching, the registry job polls npm for the exact published version for up to 12.5 minutes, including downloading its tarball, so the registry never checks while npm is still propagating the package. The tag is a separate job so that a tag failure can be retried on its own with Re-run failed jobs — re-running the publish is not an option, because npm versions are immutable and publishing the same one twice fails outright.

Both downstream jobs are gated on a published output that the publish step sets only after npm publish --tag preview succeeds. This ensures tagging runs only after publication and the registry update runs only after that exact version can also be downloaded from npm.

A stable and a preview dispatch can never collide — a release merge publishes stable and skips the preview, every other push does the reverse — so the registry sees exactly one dispatch per published version.

npm install @agentclientprotocol/claude-agent-acp@preview
npm view @agentclientprotocol/claude-agent-acp dist-tags
git ls-remote --tags origin 'refs/tags/*preview*'

The version is the package.json version with the patch incremented, plus -preview.N: with main at 0.73.0 the previews are 0.73.1-preview.1, 0.73.1-preview.2, and so on. N restarts at 1 whenever release-please moves package.json, which keeps the sequence monotonic whichever way the next release goes — a patch release makes the next base 0.73.2, a minor makes it 0.74.1, and both sort above every 0.73.1-preview.*.

0.73.1-preview.4 is not a promise that 0.73.1 will ship. The base is a patch bump because that is the only choice depending solely on package.json, which release-please only ever increases. Using release-please's predicted next version would read better but that prediction moves mid-flight: a fix: opens a 0.73.1 release PR, a later feat: moves it to 0.74.0, and N would reset under previews that were already published.

N comes from scripts/next-preview-version.mjs, which takes the larger of two sources. The npm registry says what is taken — npm versions are immutable and stay reserved even after npm unpublish, so reusing one is a hard failure — but it is CDN-served and can lag a publish by minutes. The git tags this job writes are strongly consistent and cover that window. The job publishes before it tags, so a version can exist on npm without a tag but never the reverse; that is why a registry read failure aborts the run rather than falling back to the tags alone.

Two pushes landing together cannot collide, because the job takes a concurrency group. GitHub keeps only one run pending per group, so a third push arriving while one preview runs and another waits drops the waiting one — that commit simply gets no preview.

latest stays put because the job passes npm publish --tag preview. Without it npm would move latest onto the preview: --tag defaults to latest even for a semver prerelease. Right after a release the preview dist-tag can name a version below latest until the next push lands; that is cosmetic.

Release merges are excluded by checking the head commit's author and the subject release-please generates. Both are checked, either is enough, and the cost of a miss is one wasted version number plus a preview tag briefly pointing at already-released code — latest is untouched. Previews start directly on pushes to main, without waiting for CI or the release-please job. The commit checks let previews run independently of release-please's outputs.

To publish a preview by hand from any commit:

gh workflow run publish.yml --ref main \
  -f channel=preview -f ref=<commit-or-branch> -f publish_npm=false

--ref main is required: the release environment only accepts protected branches, so a dispatch from anywhere else is rejected before the job starts.

How the version is chosen

Squash merges use the PR title as the commit subject, so the PR title decides the next version. conventional-prs.yml rejects titles release-please would not understand.

PR title prefix	Effect
fix:, perf:, revert:, docs:	patch, e.g. 0.66.0 → 0.66.1
feat:	minor, e.g. 0.66.0 → 0.67.0
any of the above with !, or BREAKING CHANGE	minor while below 1.0.0
chore:, ci:, build:, test:, refactor:, style:	no release on their own

Breaking changes bump the minor rather than the major because bump-minor-pre-major is set in release-please-config.json and the package is still below 1.0.0. That is deliberate: it keeps a single ! in a PR title from shipping 1.0.0 by accident.

Note that config-file only takes effect while the workflow does not pass a release-type input to the action — with release-type set, the action ignores the config entirely. The release type is declared inside the config instead.

release-type also switches release-please from Manifest.fromManifest to Manifest.fromConfig, which is a second and sharper reason never to set it. On the manifest path the previous release is found by an exact string match against the version in .release-please-manifest.json, which is why the v<x>-preview.<n> tags are invisible to it. On the config path release-please instead sorts every candidate tag and release descending and takes the highest — and there the preview tags would be candidates.

Because the config is what is read, it also has to say "include-component-in-tag": false. Left at its default, release-please derives a component from the package name and tags claude-agent-acp-vX.Y.Z instead of vX.Y.Z. That renames the tag every step here looks up, and because no tag under the new scheme exists, it also walks the entire commit history into the changelog rather than just what landed since the last release. The preflight checks the tag release-please is going to use, so this cannot reach a published release.

Releasing 1.0.0 is therefore an explicit act: add "release-as": "1.0.0" to release-please-config.json in its own PR, release, then remove it again.

Recovering a stalled release

The release PR merged but nothing was tagged

The preflight fails with release-please is jammed. While a merged release PR still carries autorelease: pending, release-please refuses to open any new release PR at all, so every later release stalls silently until this is cleared.

Take the release notes release-please already wrote into the changelog, create the missing release, then move the label the way release-please would have:

awk '/^## \[<version>\]/{f=1;print;next} /^## \[/{f=0} f' CHANGELOG.md > notes.md
gh release create "v<version>" --target <merge-commit-sha> --notes-file notes.md
gh pr edit <pr-number> --remove-label "autorelease: pending" \
  --add-label "autorelease: tagged"

Then publish the tag as described below.

The tag exists but npm or the registry is missing

npm publishes through OIDC from inside the workflow, so this cannot be done from a laptop. Re-run the publish workflow against the existing tag:

gh workflow run publish.yml -f ref="v<version>" -f publish_npm=true

npm versions are immutable. If the package already published and only the registry update failed, pass -f publish_npm=false so the run skips publishing and only re-dispatches the registry update.

A preview published but the commit was not tagged

Only the publish is irreversible, so re-run just the tag job:

gh run rerun <run-id> --failed

Or Re-run failed jobs on the run in the web or mobile UI. This re-runs publish-tag-preview alone and leaves the successful publish untouched, which matters because re-publishing an immutable npm version would fail.

If the re-run reports that it received no version or commit, the run's carried over job outputs are gone and it cannot tag anything safely. Do it by hand instead, taking the version from the publish job's log:

gh api "repos/$(gh repo view --json nameWithOwner --jq .nameWithOwner)/git/refs" \
  -f ref="refs/tags/v<version>" -f sha="<commit-sha>"

Either way nothing is broken in the meantime: the next preview still picks the right N once the registry CDN catches up. The tag is how that number is known immediately.

Credentials

Secret	Used for
RELEASE_PLZ_APP_ID, RELEASE_PLZ_APP_PRIVATE_KEY	App token for release PRs and tags, so they can trigger workflows
REGISTRY_UPDATER_APP_ID, REGISTRY_UPDATER_APP_PRIVATE_KEY	App token scoped to the registry repository

Publishing to npm uses OIDC trusted publishing, so there is no npm token. All release jobs run in the release environment.

npm binds a trusted publisher to one repository, one workflow filename and one environment, and a package may only have one such binding. That is why preview publishing is another job inside publish.yml rather than a workflow of its own: a separate file would fail to authenticate, and registering it would cost the stable path its publisher.