[irisitymichaelgrundberg]

What

Paths ending in .diff or .patch are now clickable in the terminal and in the response viewer, the same as .txt or .json paths.

Why

Claude often writes a diff for review into its scratchpad and prints the path, for example /tmp/claude-1000/<project>/<session>/scratchpad/resolution.diff. That path rendered as plain text, because neither file-path link pattern had a diff or patch extension. Over a remote connection, a plain-text path leaves no easy way to read the file.

The server side already handles both extensions. TEXT_ATTACHMENT_EXTENSIONS is EDITABLE_EXTENSIONS, which lists diff and patch, so an out-of-workspace path registers as a text attachment and is served as inert text/plain with nosniff.

Change

• src/web/public/constants.js adds diff|patch to the extension group of FILE_PATH_LINK_PATTERN and of RELATIVE_FILE_PATH_LINK_PATTERN. The two must stay equal, and an existing test pins that.
• test/link-provider-regex.test.ts adds a scratchpad .diff path and a .patch path to the cases the rooted pattern must link.

Testing

• npm run typecheck, lint, format:check, check:frontend-syntax and check:browser-excludes pass.
• npm test passes on a clean npm ci of this branch.
• On a dev server with its own instance, POST /api/sessions/:id/attachments accepted a /tmp/.../resolution.diff, and its /raw route returned 200 with text/plain; charset=utf-8 and nosniff.
• In headless Chromium on the served page, findFilePathLinks() linked the full path out of the sentence ... scratchpad/resolution.diff., without the trailing full stop, and linked a relative ./fixes/one.patch.

🤖 Generated with Claude Code

[Ark0N]

Thanks @irisitymichaelgrundberg, this is a nice small fix: paths ending in .diff or .patch are now clickable in both the terminal and the response viewer, so an agent's review diff in its scratchpad is one click away instead of a copy-paste.

I traced every click path and it holds up. The out-of-workspace case goes through the attachment routes, which already allowlist both extensions (TEXT_ATTACHMENT_EXTENSIONS is EDITABLE_EXTENSIONS) and serve them as text/plain with nosniff, and the in-workspace case uses the routes it always did. Typecheck, lint, format, the frontend checks and the link tests are all green here.

One bonus you did not mention: the hard-wrap joiner reads its extension list off the same pattern, so a long scratchpad .diff path that Claude Code wraps across two rows now links as one path.

One thing changed since you opened this: #621 landed and added tsv and zip to the same two extension groups in constants.js, so the branch now conflicts there. The resolution is to keep both, your diff|patch and master's tsv and zip. If you rebase, great; otherwise I'll resolve it when I merge. Apart from that, nothing to change. Two notes for later, neither is on you:

• src/web/public/constants.js:2103: the relative pattern now also links method calls like df.diff(, np.diff( and mock.patch(. That is the same trade-off console.log( and res.json( already make on master, so it does not hold this PR; a lookahead that refuses a match followed by ( would fix the whole class in a separate change.
• test/file-path-link-forms.test.ts:77: the trailing full stop and the relative ./fixes/one.patch forms you checked by hand would fit there as one-line cases if you ever touch this again.

This goes in with the next release.

[Ark0N]

Merged and shipped in 1.43.0. Thanks @irisitymichaelgrundberg! I resolved the constants.js conflict with #621 when merging, keeping your diff|patch and master's tsv and zip in both patterns, and the new parity test from #653 now guards that list.