Worktree Stacked Feature PR

Create multiple implementation PRs from a single progress/planning PR using git worktree and parallel subagents.

Contract

Prereqs:

• •Run inside the target git repo.
• •git and gh available on PATH, and gh auth status succeeds.
• •Working tree is clean in the primary repo checkout before starting.
• •You have a progress planning PR number (the docs-only PR), and it is approved and mergeable.
• •You intend to create 2+ implementation PRs that can be worked on in parallel (typically stacked).

Inputs:

• •Planning PR number (the progress PR).
• •Progress file path: docs/progress/<YYYYMMDD>_<feature_slug>.md
• •Implementation plan file path (optional but recommended): docs/plans/<...>-plan.md
• •PR split spec (recommended):
  • •PR 1: Sprint 1 (base: main)
  • •PR 2: Sprint 2–4 (base: PR 1 branch) — stacked PR
  • •Add more PRs if needed (e.g., PR 2a/2b/2c) to reduce conflicts.

Outputs:

• •Planning PR merged and closed; head branch deleted by default.
• •Planning PR body Progress link patched to blob/<base-branch>/... so it survives branch deletion.
• •2+ implementation branches created.
• •2+ implementation PRs opened (draft by default), each referencing:
  • •the progress file (stable link on base branch)
  • •the planning PR (#<number>)
• •Worktrees created for each branch, ready for subagent work.

Exit codes:

• •0: success
• •1: validation or workflow failure (see Failure modes)

Failure modes:

• •Planning PR is still draft → stop; mark ready first.
• •Planning PR not mergeable / checks failing → stop; fix or explicitly accept bypass.
• •Worktree paths already exist → stop; remove/rename; run git worktree prune.
• •Two PRs modify the same files heavily → split into more PRs (Sprint 2a/2b/2c) or serialize.

Overview

This skill creates multiple implementation PRs from a single progress/planning PR, using:

• •gh + git for PR/branch management
• •git worktree for parallel local checkouts
• •subagents for parallel implementation (one worktree per subagent)

This skill is designed to “follow” a progress PR created by create-progress-pr, and is aligned with handoff-progress-pr (merge planning PR + keep Progress links stable), but extends the workflow to kick off multiple implementation PRs at once.

Worktree usage policy (explicit rules)

Directory layout

• •Worktrees root (default): <repo_root>/../.worktrees/<repo_name>/
  • •Example: if repo root is /work/graysurf/agent-kit, worktrees go to /work/graysurf/.worktrees/agent-kit/
• •Worktrees root override: pass --worktrees-root <path> to create_worktrees_from_tsv.sh when you need a different root.
• •Worktree path: <worktrees_root>/<worktree_name>/
  • •worktree_name must be filesystem-safe: replace / with __.
  • •Example: branch feat/notifications-sprint1 → worktree feat__notifications-sprint1

Commands (canonical)

• •List worktrees:
  • •git worktree list --porcelain
• •Add a worktree + create branch:
  • •git worktree add -b <branch> <path> <start-point>
  • •<start-point> is usually main (PR1) or feat/<pr1-branch> (stacked PR2).
• •Remove a worktree (after PR is created/merged):
  • •git worktree remove <path>
  • •git worktree prune

Safety rules

• •Never run “global refactors” across multiple worktrees in parallel.
• •Do not run yarn install in multiple worktrees concurrently (contention + huge disk churn).
• •Each subagent must:
  • •touch only its assigned worktree directory
  • •commit only on its assigned branch
  • •push only its assigned branch
• •When using stacked PRs:
  • •PR2 must be based on PR1 branch, and its PR base must be PR1 branch (not main) until PR1 merges.

Workflow

Step 0 — Preflight (must pass)

1. •Confirm planning PR details:
   • •Not draft, mergeable, checks green (or explicitly accepted to bypass).
2. •Confirm progress file path:
   • •Prefer parsing the planning PR body ## Progress link.
3. •Decide PR split(s):
   • •Default: (Sprint 1) + (Sprint 2–4 stacked on Sprint 1).

Step 1 — Handoff (merge) the planning PR

Use the same outcome as handoff-progress-pr:

1. •Merge planning PR into base (main) and delete the head branch.
2. •Patch the planning PR body Progress link so it points to blob/main/... after merge.

If you have the helper script available:

• •bash $AGENTS_HOME/skills/workflows/pr/progress/handoff-progress-pr/scripts/handoff_progress_pr.sh --pr <planning_pr_number>

Step 2 — Create branches + worktrees (stacked)

Create worktrees from a TSV spec (recommended). Example spec:

• •See: references/pr-splits.example.tsv

Create worktrees:

• •bash $AGENTS_HOME/skills/workflows/pr/progress/worktree-stacked-feature-pr/scripts/create_worktrees_from_tsv.sh --spec $AGENTS_HOME/skills/workflows/pr/progress/worktree-stacked-feature-pr/references/pr-splits.example.tsv
• •Optional flags:
  • •--worktrees-root <path> to override the default worktrees root.
  • •--dry-run to print planned worktrees without creating them.

Step 2.5 — Create the PRs (draft) after the first commit

This skill expects each implementation branch to contain at least one commit before opening a PR.

Per branch/worktree (repeat for each PR):

1. •Make the first change (it can be a small scaffold commit).
2. •Commit using semantic-commit / semantic-commit-autostage (do not run git commit directly).
3. •Push the branch.
4. •Open the draft PR with the correct base branch:
   • •PR1 base: main
   • •PR2 base: PR1 branch (stacked)

Recommended PR body includes:

• •Progress link: https://github.com/<owner>/<repo>/blob/main/docs/progress/<file>.md
• •Planning PR: - #<planning_pr_number>

Step 2.6 — Patch the planning PR with implementation links (recommended)

After opening the implementation PRs, update the merged planning PR body to include:

• •Sprint 1 PR link/number
• •Sprint 2–4 PR link/number (and note it is stacked, if applicable)

This makes the planning PR a stable entry point from the progress file.

Step 3 — Parallelize implementation with subagents

Spawn one subagent per worktree/PR. Each subagent must receive:

• •Worktree path
• •Branch name
• •Scope (which Sprint(s)/tasks to implement)
• •Validation commands to run
• •PR base branch (for stacked PRs)
• •Required PR body metadata:
  • •Progress link: https://github.com/<owner>/<repo>/blob/main/docs/progress/<file>.md
  • •Planning PR: - #<planning_pr_number>

Subagent completion criteria (required):

• •Branch pushed to origin
• •Draft PR opened with correct base branch
• •Commands run (or “not run (reason)” documented in PR body)
• •Short report: files changed + what’s complete vs blocked

Step 4 — Integration + conflict management

• •Prefer stacked PRs to resolve dependencies cleanly.
• •If PR2 needs PR1 changes:
  • •keep PR2 base on PR1 branch until PR1 merges
  • •after PR1 merges, rebase PR2 onto main and update the PR base

Step 5 — Cleanup

• •Keep worktrees while PRs are active if you expect follow-up commits.
• •Remove worktrees after PR merge (recommended):
  • •git worktree remove <path>
  • •git worktree prune
• •Optional helper (preview first, then confirm):
  • •bash $AGENTS_HOME/skills/workflows/pr/progress/worktree-stacked-feature-pr/scripts/cleanup_worktrees.sh --prefix <branch-prefix> --dry-run
  • •bash $AGENTS_HOME/skills/workflows/pr/progress/worktree-stacked-feature-pr/scripts/cleanup_worktrees.sh --prefix <branch-prefix> --yes

Failure modes (and what to do)

• •Planning PR is still draft → stop; mark ready first.
• •Planning PR not mergeable / checks failing → stop; fix or explicitly accept bypass.
• •Worktree paths already exist → stop; remove/rename; run git worktree prune.
• •Two PRs modify the same files heavily → split into more PRs (Sprint 2a/2b/2c) or serialize.