[Maintenance] Trigger opencode agent on PR review comments containing /oc

[RussellSB]

Problem

The OC agent workflow doesn't trigger when /oc appears in PR review comments — only PR body comments work. Observed in PR #232 where a review with /oc was submitted but nothing happened.

Root cause

The workflow uses issue_comment events, which only match PR/issue body comments. Review comments use a different event type (pull_request_review or pull_request_review_comment) that isn't in the trigger.

Solution

Add pull_request_review (or pull_request_review_comment) as an additional trigger in the workflow YAML.

Branch target

Targets main, not develop:

git checkout -b ci/oc-review-comment-trigger origin/main

Commit type note

Use chore: or ci: prefix — not fix: or feat: — to avoid triggering a semantic-release bump.

Acceptance criteria

• /oc in PR review comments triggers the OC agent workflow
• No false negatives on valid /oc command formats
• Commit uses chore: or ci: prefix

Backlinks

• PR: docs(whats-new): add what's new entry for v1.4.0-dev.1 #232 (where the failure was observed)
• Related: [Maintenance] Fix OC agent trigger reliability and response failures #240 (closed — broader trigger reliability, did not address review comments)

[coderabbitai]

🔗 Related PRs

#173 - ci: add opencode access github app [merged]
#207 - ci: update opencode job conditions and permissions [merged]
#209 - ci: grant contents write permission to OpenCode agent [merged]
#220 - ci: correct forked branch pipeline [merged]
#244 - chore: improve OC agent reliability for remote PR-triggered sessions [merged]

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[RussellSB]

Investigated

The opencode action's runtime (packages/opencode/src/cli/cmd/github.handler.ts:148-150) only supports these events:

issue_comment, pull_request_review_comment, issues, pull_request, schedule, workflow_dispatch

pull_request_review (review body on Submit) is not in the allowlist. When triggered, the action throws Unsupported event type: pull_request_review — the error is caught but no comment is posted because commentId hasn't been set yet.

What works

• /oc in PR conversation thread → issue_comment
• /oc on a specific code line (Files tab) → pull_request_review_comment

What doesn't work

• /oc in review body on Submit review → pull_request_review (not supported upstream)

Fix

Removed pull_request_review trigger and review body checks from the if condition in PR [LINK_TO_PR]. Added a comment block documenting the supported events.