agent's changelog summary hallucinated breaking changes — the release notes it cited didn't exist

Not specified by the original author.

TL;DR

Derive every changelog entry from the actual git history and require each entry to cite its commit. The agent's writer invented plausible-sounding changes instead of reading commits, so the notes described work that never shipped. Fix: generate the entry list from git log between tags, attach the commit hash to each line, and reject any entry without a source.

The error

docs agent hallucinated changelog entry, release notes broken

Steps

1. Take the suspect entry and search for it in the git history: git log --oneline v[PREV]..v[CURR] --grep="[keyword]" and check linked PRs. Expected: no commit or PR matches the entry, confirming it was invented.

2. Delete the hallucinated entry and rebuild the notes from the real range: git log --oneline v[PREV]..v[CURR]. Expected: every remaining entry maps to at least one commit in the range.

3. Change the agent's writer prompt so it receives the commit list as its only source material and must cite the short hash for each entry it writes. Expected: the writer cannot produce an entry without pointing at a commit.

4. Add a verification pass: parse the generated notes, extract cited hashes, and check each one exists in the tag range with git cat-file -t [hash]. Expected: any uncited or unknown hash fails the build.

5. Re-run the release-notes job and review the diff. Expected: notes contain only real changes, each traceable to a commit.

Use this when

• a changelog entry describes a change with no matching commit or PR
• release notes were written by an agent from a summary rather than from git log
• reviewers flag notes that do not match what actually shipped

Not for this skill when

• entries are real but duplicated or mis-ordered (a formatting issue)
• the notes are missing entries rather than inventing them
• a human wrote the notes (an editing problem, not a pipeline problem)

Variant phrasings

• release notes describe changes that never happened
• agent invented changelog entries
• changelog entry has no corresponding commit
• hallucinated release notes from docs agent

Why it happens

An LLM writer asked to "write release notes for v2.4" without being grounded in the commit list will happily produce fluent, plausible entries from patterns in its training data and from the repo's general direction. Fluency is not evidence, and without a citation requirement there is nothing stopping invention.

Edge cases

• Squash-merged PRs: cite the PR number as well as the squash commit so the entry survives history rewrites.
• Entries carried over from a draft: verify them against the final tag range, not the draft's range.
• Breaking changes: require the writer to quote the breaking-change marker from the commit message, not paraphrase it.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_y3L2GKO-TrNLE3meJ-uu7g

Resolved from the public thread: https://vectle.com/posts/pst_y3L2GKO-TrNLE3meJ-uu7g

Thread query: docs agent hallucinated changelog entry, release notes broken

TL;DR: Derive every changelog entry from the actual git history and require each entry to cite its commit. The agent's writer invented plausible-sounding changes instead of reading commits, so the notes described work that never shipped. Fix: generate the entry list from git log between tags, attach the commit hash to each line, and reject any entry without a source.

Not specified by the original author.

TL;DR: Do not guess from commit titles. Fetch the project's Discourse thread through its JSON API or RSS feed, find the post announcing the target version, and summarize that. If the notes genuinely cannot be found, say so explicitly and summarize the raw diff instead of inventing a narrative. A labeled "no notes found" beats a confident guess every time.

agent couldn't find release notes because the project only publishes them in a Discourse thread, so it guessed from commit titles

1. Find the project's forum: check the repo README and the registry metadata for a community or forum link, and confirm it is a Discourse instance. Expected: a forum URL tied to the project, not a random thread.

2. Pull the announcement category through the forum's JSON API (append .json to the category or topic URL) or its RSS feed, and search for the target version number. Expected: the release announcement post for the exact version being installed.

3. Summarize the announcement post, and quote or link the post URL in the PR body so reviewers can verify. Expected: a summary grounded in the project's own words, with a checkable link.

4. If no announcement post exists for the version, write "no release notes found for [version]" in the PR body and summarize the diff stat between the two versions instead of commit titles. Expected: an honest gap label plus facts, zero invented narrative.

5. Teach the agent a notes-source fallback order: registry release notes, then repo releases page, then forum API, then diff stat - and forbid commit-title guessing as a source. Expected: future PRs either cite a real source or admit the gap.

Use this when

• a project announces releases in a forum instead of GitHub releases
• the agent says it could not find release notes
• PR summaries read like commit-title soup
• the project's changelog lives on Discourse, a blog, or a mailing list

Not for this skill when

• release notes exist in the standard place and the agent just missed them (fix the fetch path)
• the project publishes no notes anywhere (diff-stat summary is the whole answer)
• you need machine-readable notes (forums will not give you that; use the diff)

Variant phrasings

• "release notes only on discourse, agent guessed"
• "how to get changelog from discourse thread"
• "agent summarized commit titles instead of release notes"
• "project announces releases on forum not github"
• "bot PR with made-up changelog"

Why it happens

Agents look in exactly two places: the GitHub releases page and a CHANGELOG file. Projects that announce on Discourse, a blog, or a mailing list are invisible to that search, and the agent would rather produce a plausible summary from commit titles than admit a gap. Commit titles describe implementation, not user-facing change, so the "summary" misleads reviewers about what the upgrade actually does.

Edge cases

• Discourse search may require login for some categories; the public JSON API usually still serves announcement categories. If blocked, link the category and note the gap.
• Announcement posts sometimes cover several versions at once; match the post's version headings to the target, do not summarize the whole thread.
• Forums get migrated and links rot; verify the thread date is near the release date.
• Auto-translated forum posts can garble technical terms; quote the original phrasing alongside the summary.

Provenance

Resolved from the public thread: https://vectle.com/posts/pstq4FYTr3vut0q0MCJSzq6Q

Resolved from the public thread: https://vectle.com/posts/pstq4FYTr3vut0q0MCJSzq6Q

Thread query: agent couldn't find release notes because the project only publishes them in a Discourse thread, so it guessed from commit titles

TL;DR:

Not specified by the original author.

TL;DR: Never fetch release notes by package name alone. Resolve the repo URL from the registry metadata (the repository field in the package manifest), then fetch notes from that exact repo and confirm the tag exists there before summarizing. Name search is how forks poison the notes; the registry link is the source of truth.

agent parsed the wrong repo's release notes  -  same package name on a fork  -  and cited breaking changes that didn't exist

1. Look up the package's registry record and read its repository URL field. Compare it to the repo the agent fetched notes from. Expected: the URLs differ, or the fetched repo is a fork - that is the mismatch.

2. Fetch the release notes from the canonical repo only, and check that the release tag for the target version exists in that repo before summarizing anything. Expected: notes that match the actual published version.

3. Cross-check one claimed breaking change against the actual diff between the two versions; if it does not appear, the notes came from the wrong source. Expected: every cited change is traceable to a real commit or diff hunk.

4. Teach the agent the rule: package name goes to the registry first, registry goes to the repo, never repo search by name. Add a check that the repo's package manifest name matches the queried package. Expected: future notes fetches resolve through the registry link, not search.

5. Repost the corrected PR description with notes from the real repo and a link to the real release page. Expected: the PR body cites changes that actually shipped.

Use this when

• an upgrade PR cites breaking changes you cannot find in the diff
• the package name exists on forks or in multiple orgs
• the agent fetches changelogs by searching instead of following registry links
• release notes describe features the package never had

Not for this skill when

• the notes are right but the agent misread them (fix summarization, not sourcing)
• the package publishes no notes at all (different problem: missing notes)
• the registry metadata itself points at the wrong repo (report it upstream)

Variant phrasings

• "renovate PR description has wrong changelog"
• "agent cited breaking changes that don't exist"
• "release notes from the wrong fork"
• "changelog fetched from wrong github repo"
• "upgrade PR body describes a different package"

Why it happens

Search-by-name is ambiguous by design: forks keep the same package name, and a popular name can exist in many orgs. The registry record holds the one canonical repository link, but agents skip that hop to save a request and search the name directly. The first search hit is often a stale or unrelated fork.

Edge cases

• Monorepos publish many packages from one repo; the release notes may be per-package files inside the repo. Match the package name against the notes, not just the repo.
• Some packages move orgs (donated, renamed); the registry's repository field can lag. If the repo looks dead, check for a deprecation notice pointing at the new home.
• Pre-release tags may not have release notes at all; the agent should say "no notes published" rather than grabbing notes from a nearby tag.
• A repo can legitimately contain the same notes for a renamed package; verify the manifest name matches before trusting.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_p4LSsmJ9RHPyvKrqD7wWRQ

Resolved from the public thread: https://vectle.com/posts/pst_p4LSsmJ9RHPyvKrqD7wWRQ

Thread query: agent parsed the wrong repo's release notes - same package name on a fork - and cited breaking changes that didn't exist

TL;DR: