feat(server): make the worktree branch prefix configurable

[RaitP1]

What Changed

• Added a global setting, worktreeBranchPrefix, default t3code/. It is applied when the first turn renames a worktree thread's branch.
• Moved buildGeneratedWorktreeBranchName into packages/shared/src/git.ts, which deletes a verbatim copy of sanitizeBranchFragment in ProviderCommandReactor.ts.
• Added a "Worktree branch prefix" row to Settings → General.

Why

Every generated worktree branch is forced under a hard-coded t3code/ prefix. A team whose repository requires feat/ or fix/ cannot follow its own convention.

The configured value goes in front of the generated name verbatim, so feat/, rait-, and an empty string all work without a special case. The default does not change, so no branch name changes until a user opts in.

The temporary t3code/<8 hex> branch keeps its fixed name on purpose: the clients build that name, including the mobile offline outbox drain, and four call sites match on its shape.

Deliberately out of scope: a project-scoped prefix in t3.json, the separate feature/ auto-branch, and the pre-existing silent rename failure when an existing branch shadows the prefix.

Related: #272. #3954 proposes the same setting and has been open longer — close this one if that lands first.

UI Changes

The new row in Settings → General. Same window, viewport, theme, and settings state in both captures; only the checkout differs.

Before

After

Checklist

• This PR is small and focused
• I explained what changed and why
• I included before/after screenshots for any UI changes
• Not applicable — the change has no animation or interaction

Written by Claude Opus 5 in Claude Code.

---

Note

Low Risk
Default prefix is unchanged; impact is limited to optional git branch naming on first turn plus settings UI, with sanitization and tests.

Overview
Adds worktreeBranchPrefix to server settings (default t3code/, patchable including empty string) and wires it into first-turn worktree renames from temporary t3code/<hex> branches.

buildGeneratedWorktreeBranchName and sanitizeBranchPrefix move to @t3tools/shared/git, replacing the reactor’s local builder so names use the configured prefix, strip echoed t3code/ or prefix namespaces, and sanitize fragments. ProviderCommandReactor passes settings.worktreeBranchPrefix when renaming after branch-name generation.

Settings → General gets a Worktree branch prefix field (commit sanitizes input), reset/dirty tracking, and search entry. Contract and shared git tests cover defaults and naming edge cases; the reactor test asserts feat/safer-reconnect-backoff when prefix is feat/.

^{Reviewed by Cursor Bugbot for commit 2898611. Bugbot is set up for automated code reviews on this repo. Configure here.}

Note

Make the worktree branch prefix configurable via server settings

• Adds worktreeBranchPrefix to the ServerSettings schema (defaulting to "t3code/") and ServerSettingsPatch, allowing users to override the prefix used for generated worktree branch names.
• Introduces sanitizeBranchPrefix and buildGeneratedWorktreeBranchName in packages/shared/src/git.ts; the builder normalizes the prefix, strips echoed namespaces, sanitizes the fragment, and falls back to "update" when the sanitized fragment is empty.
• Adds a UI control in General Settings (SettingsPanels.tsx) to view, edit, and reset the prefix, with input sanitized via sanitizeBranchPrefix before saving.
• Makes the prefix discoverable via settings search under the id "worktree-branch-prefix".
• Behavioral Change: ProviderCommandReactor now calls the shared buildGeneratedWorktreeBranchName instead of a local implementation, applying the user-configured prefix and additional sanitization rules.

^{Macroscope summarized 2898611.}

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on this repository. Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Repository UI

Review profile: CHILL

Plan: Pro Plus

Run ID: 985bb71c-7f2b-40fe-b05c-9b9b184e742a

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands.}

[macroscopeapp]

One finding in the settings search catalog: the new "Worktree branch prefix" entry redirects search navigation to another row's anchor even though the new row renders its own anchor id.

^{Posted via Macroscope — UI Consistency}

[macroscopeapp]

Approvability

Verdict: Approved e6ecb1b

Simple additive feature making the worktree branch prefix configurable. The schema change is backwards-compatible with a sensible default, the refactoring is mechanical (parameterizing existing logic), and tests are comprehensive.

^{You can customize Macroscope's approvability policy. Learn more.}

[CDVolvik]

git.test.ts + settings.test.ts on the PR files: 54/54.

Configurable worktree prefix belongs in server settings, not a hardcoded t3code/. Watch the sanitizer — a user-typed prefix has to stay a valid git ref fragment. The tests cover the contract trim; I did not create a worktree with a hostile prefix. MERGEABLE.