Pull Request Review & Collaboration

px0 checks out a pull request’s complete source tree and presents it like any local workspace: full codebase navigation, symbol outline, LSP code intelligence, and full-text regex search. Reviewers get a diff scoped to the pull request’s merge-base, real-time coding agent synchronization, inline line comment drafting, AI batch application, in-app merge controls, conflict resolution with AI, and the full Git panel to stage, commit, push fixes back to the PR’s own branch, or pull in new commits pushed while reviewing.

px0 supports four major git forges using the exact same interface: GitHub, GitLab (gitlab.com and self-hosted), Gitea / Forgejo / Codeberg, and Bitbucket Cloud.

For a quick 5-minute walkthrough, see Getting Started with Pull Request Review.

Opening a Pull Request

Pull request review is triggered by passing the full pull request URL directly to the CLI:

# GitHub
px0 https://github.com/owner/repo/pull/123

# GitLab (gitlab.com or self-hosted instances)
px0 https://gitlab.com/group/project/-/merge_requests/45

# Gitea, Forgejo, or Codeberg
px0 https://codeberg.org/owner/repo/pulls/7

# Bitbucket Cloud
px0 https://bitbucket.org/workspace/repo/pull-requests/9

px0 automatically prepares an isolated worktree or clone, computes the merge-base diff against the target branch, and opens a lightweight, zero-latency code viewer in your default browser.

[!NOTE] Bare PR numbers (such as px0 123) and the legacy px0 pr subcommand have been deprecated in favor of explicit URL routing (px0 <url>). Running px0 pr displays a reminder to pass the URL directly.

Preparation Progress Spinner

Because fetching metadata and checking out remote references takes a few moments, px0 displays an animated CLI spinner:

⠋ Fetching PR #123 metadata from github...
⠙ Fetching PR #123 head and preparing worktree...
⠸ Computing merge base with main...
✔ PR #123 checked out (Refactor auth token resolution)

Merged PR Handling

If the pull request is already merged:

• px0 detects its merged status from the API and opens it immediately without blocking or prompting.
• Both the CLI checkout summary and the browser review header display a prominent purple Merged pill badge.

Multi-Session Process Isolation

Each pull request review runs as its own isolated process on an ephemeral port. Running px0 https://github.com/owner/repo/pull/456 while another PR review or local workspace is open will never interfere with existing sessions.

From inside any running px0 browser session, you can also launch another pull request review via the Command Palette:

1. Press Cmd+K or Ctrl+K.
2. Select Git: Open Pull Request…
3. Paste the pull request URL. px0 launches a fresh review process in a new browser tab.

Scoped Merge-Base Diffing & Isolated Reviewer Edits

Unlike standard working tree diffs that compare against HEAD, PR reviews calculate diffs against the commit where the PR branch diverged from the base branch (the merge-base):

• The Changes toggle in the sidebar defaults to all files touched by the pull request.
• Press Cmd+D or Ctrl+D on any file to open side-by-side or unified diffs.
• The diff is computed against the merge-base between the PR head and its target branch, exactly mirroring the diff shown on GitHub or GitLab.
• Full codebase files remain fully browsable. You can jump to callers, inspect definitions, and search usages across untouched files without having to switch git branches locally.

Isolated Reviewer Diffs

When reviewing a PR, you may test local changes or delegate fixes to an AI coding harness (Alt+E). px0 isolates your working-tree edits from the pull request author’s commits:

• Collapsible Diff Sections: The diff viewer separates frozen PR changes (PR Changes (Frozen)) from your working edits (Your Changes), each with its own collapse toggle.
• “YOU” Tree Badge: Files modified locally by the reviewer receive a bright YOU badge in the sidebar tree, and directory branches display dirty dots so your changes stand out.
• Selective Staging Controls: Staging checkboxes in the PR tree are hidden by default for original PR files and appear only for files you modify, preventing accidental restaging of original PR code.
• Protected Comment Anchoring: Local reviewer diff sections are marked non-reviewable, ensuring inline comment drafts always anchor cleanly to upstream lines rather than local scratch edits.

Multi-Stage PR Review Workflow & Workplace Modes

Starting in version 0.1.21, px0 introduces dedicated workplace modes and an automated, multi-stage review workflow engine:

1. Code Mode vs. Review Mode (Mod+Shift+C / Mod+Shift+V)

At the top of the main editor area, the mode switcher lets you toggle between:

• Code Mode (Cmd+Shift+C / Ctrl+Shift+C): Traditional file tree browsing, code editing, and diff inspections.
• Review Mode (Cmd+Shift+V / Ctrl+Shift+V): Dedicated review pipeline dashboard that runs sequential AI review stages across the PR.

A status dot in the header mode button indicates background review progress while you work in Code Mode.

2. Multi-Stage Review Pipeline

The review workflow guides your local AI harness through sequential review stages answering key questions:

1. What this PR does: High-level problem overview, key architectural shifts, and list of altered components with file citations.
2. Performance Impact: Algorithmic complexity, memory allocations, blocking I/O, database queries, and mutex/lock contention.
3. Architecture & Quality: Modularity, maintainability, design patterns, silent failure risks, and breaking API changes.
4. Testing & Edge Cases: Test coverage verification, missing edge scenarios, error paths, and suggested automated tests.

3. Pipeline Controls & Customization

• Sequential Execution: Click Run Review to execute all stages in sequence, or run from a specific stage.
• Inline Customization: Click any stage title or question to edit the underlying AI prompt, toggle whether to pass prior stages’ context, or assign a specific harness/model.
• Add / Remove Stages: Add custom review stages tailored to your project’s checklist (e.g. security audits, migration verifications) or delete unneeded stages.
• Layout Toggles: Switch between horizontal side-by-side or vertical split layouts to suit your screen dimensions.
• Direct Citation Links & Return Pill: Clickable path:line citations in review findings open the target file and position in the editor. A floating Return to Review pill appears at the bottom-right, allowing you to jump back to Review Mode with one click.

Inline Comments & Review Workflows

Reviewing code requires clear communication and quick feedback loops. px0 provides two convenient mechanisms to draft inline comments:

1. Line Hover Thread Icon

Hover over any line number in the source editor or diff viewer:

• A thread icon appears in the gutter.
• Clicking it opens a context menu with options for that line:
  • Add Review Comment: Opens the review comment composer for that line.
  • Edit Inline: Prompts your local AI coding harness to edit those lines directly.
  • Start Thread: Opens a persistent conversation with your agent anchored to that line.

2. Selection Action (Alt+R / Option+R)

Select any range of lines across the code viewport or diff viewer:

• The footer selection bar displays a dedicated Comment button with shortcut Alt+R (or Option+R on macOS).
• Pressing Alt+R opens the comment composer pre-targeted to your selected line range.
• Enter your comment and press Cmd+Enter or Ctrl+Enter to save the draft.
• Gutter markers (💬) and the top PR comments panel update immediately.

Persistent Draft Comment Storage

Draft review comments are saved in persistent session files located at $XDG_STATE_HOME/px0/pr-sessions/ (falling back to ~/.px0/pr-sessions/):

• Keyed to a stable identifier derived from the forge and PR (provider/owner/repo#number), not the temporary checkout path.
• Drafts survive browser reloads, workspace stops, and worktree recreations.
• Drafts remain active across tab switches, file edits, and diff toggles until explicitly submitted or deleted.

Batch Apply with Local AI Agents

When reviewing pull requests, you often identify trivial fixes, missing docstrings, error handling tweaks, or variable renames. Instead of writing them manually or waiting for the author to cycle back:

1. Draft your comments across the affected files using Alt+R or the gutter pencil icon.
2. In the PR review header bar, click Batch Apply.
3. px0 dispatches all drafted comments to your configured AI coding agent (Claude Code, Cursor Agent, Antigravity, or OpenCode).
4. The harness reads your comments as instructions and applies the edits directly to the worktree.
5. px0’s real-time file watcher catches the modifications, reloading the diff view and tab statuses live.

Submitting Formal Reviews to Remote Forges

When you are ready to post feedback back to the forge:

1. The PR review bar at the bottom of the screen (right above the comments panel) holds the review summary, verdict buttons, and merge controls.
2. Enter your top-level review summary in the review box.
3. Select your review action:
   • Comment: Submit feedback without an approval status (available to all reviewers).
   • Approve: Approve the pull request (requires repository push access).
   • Request Changes: Request changes before merging (requires repository push access).
4. Submitting posts your review summary and all drafted line comments according to forge API conventions.
5. In-session drafts are cleared upon successful submission.

Bringing PRs Up to Date & Resolving Conflicts

The first row of the PR bar shows a status pill with the forge’s answer to mergeability (Ready to merge, Checks failing, Conflicts with main, Behind main, Merge blocked, Draft, or Checking mergeability…). Clicking the pill or the Rebase with AI button next to it takes the next step (resolve or force-push). When there is no next step, clicking the pill refreshes the status.

When the PR conflicts with its base, or is behind it, click Rebase with AI (or click the status pill):

1. px0 fetches the latest base branch and prompts you in the Git panel to pick a strategy:
   • Rebase with AI: Replays PR commits on top of base for a linear history.
   • Merge with AI: Merges the base branch into the PR branch with a merge commit.
2. The chosen harness resolves conflicts, edits files, and stages the resolutions. The harness is instructed never to push.
3. Review the result in the diff viewer.
4. For rebases, px0 prompts you before force-pushing. px0 uses git push --force-with-lease so that if someone pushed to the PR branch while you were rebasing, the push is refused and remote work is never lost.

Merging the Pull Request

With push access, a split merge button sits next to Approve. The main button runs the method you used last (e.g. Squash and merge). The caret lists every method the repository allows: Create a merge commit, Squash and merge, or Rebase and merge. Clicking the merge button directly opens the merge dialog:

1. Choose or verify the merge strategy.
2. For squash merges, a checkbox lets you Rewrite commit message with AI to automatically synthesize an informative commit title and description using your local coding harness.
3. For a merge commit or squash, you can also manually edit the title and message or click Rewrite with AI to regenerate them from the PR commits and diff on demand.
4. Confirm the merge. px0 verifies that the PR head matches the exact commit you reviewed before executing the merge.

Forge Differences

The table below summarizes behavioral differences across supported git forges:

GitLab Nuances

• Submissions: GitLab has no single endpoint for batched reviews. Each draft comment creates a diff discussion thread, and the summary is posted as a note. Approve triggers GitLab’s native approval pinned to the reviewed commit SHA.
• Merge methods: Follows project settings (merge commit, fast-forward rebase, or squash). When a rebase is required, the status pill reads Behind main.
• UI wording: Labeled “PR #N” in the px0 UI rather than GitLab’s “!N” for consistency.

Gitea / Forgejo Nuances

• Submissions: Posted as a single consolidated review payload matching GitHub’s workflow.
• Replies: Gitea replies are created as comments on the corresponding line. Existing comments are rendered on the new side of the diff.
• Merge checks: Branch protection rules are validated during the merge attempt; if blocked, Gitea’s error reason is displayed in the dialog.

Bitbucket Cloud Nuances

• Checkout: Bitbucket does not publish head refs under refs/pull/, so px0 clones the source branch directly (including from forks).
• Submissions: Drafts post as individual inline comments with native threading.
• Tokens: API tokens require account email to verify push permissions. Standard workspace access tokens leave Approve and Merge hidden.

Authentication & Forge Connect Dialog

px0 discovers credentials automatically from settings and environment variables:

• GitHub: github.token in Settings, GITHUB_TOKEN, GH_TOKEN, or gh auth token.
• GitLab: gitlab.token in Settings, GITLAB_TOKEN, or glab auth CLI credentials. For self-hosted instances, configure gitlab.host.
• Gitea / Codeberg: gitea.token in Settings, GITEA_TOKEN. Hostname configured via gitea.host.
• Bitbucket: bitbucket.token and bitbucket.email in Settings, or BITBUCKET_TOKEN / BITBUCKET_EMAIL.

Connect Dialog

If you open a pull request without configured credentials, px0 operates in read-only mode and displays a No <forge> token - click to connect link in the PR bar. Clicking it opens the in-app Connect dialog:

• Guides you through generating the correct token type with precise scope instructions.
• Verifies token validity immediately on paste.
• Saves the token directly to ~/.px0/settings.json without requiring a server restart.

Keyboard Shortcuts for PR Review