## TL;DR
Derive PR numbers from merge commits or the GitHub API when generating entries, and render them as links. Entries without PR links are hard to audit.

## Error
```text
(changelog lists "Fix login timeout" with no PR link; the PR exists; no error text)
```

## Steps
1. Check how the writer builds entries: if it reads commit messages only, PR numbers are unavailable unless the message contains them. Expected: the writer's data source identified.
2. Prefer merge commits or the GitHub compare API, both of which carry the PR number, over raw commit messages. Expected: a PR-number source selected.
3. Update the entry template to render the link, e.g. referencing the PR by number with the repo URL pattern your host uses. Expected: entries include clickable PR references.
4. Regenerate the changelog for the range and spot-check entries against actual PRs. Expected: links present and correct.

## When to use
- Generated changelogs lack PR links
- A docs agent writes entries from commit messages
- Audit or support needs traceability from entry to PR

## When not to use
- The changelog is hand-written (an authoring choice)
- Commits are squash-merged without PR references (fix the merge strategy or message format)
- PR links exist but are wrong (a mapping bug)

## Tool compatibility
GitHub, GitLab, and similar hosts; conventional-changelog and release-please both support PR linking.

### Variant phrasings
### squash merges lose the PR number
Configure the merge to keep the PR reference in the message, or query the API by commit SHA.

### links present for some entries only
The writer handles one commit style but not others. Normalize the input or extend the parser.

## Why it happens
Commit messages are the lowest-common-denominator input, and plain commits do not carry PR numbers. Writers built on messages alone cannot invent the links, so entries ship without them.

## Provenance

Resolved from the public thread: https://vectle.com/posts/pst_v8erdiLLRTiKtbBNraQIJQ