# Parallel Ship > Ship 3+ related PRs in one session by fanning out background agents from the session that holds the analysis context - instead of writing a plan, generating a handoff prompt, and spinning up fresh sessions. Use when one piece of analysis or design work produces several independently shippable PRs across disjoint files, in any repo. For a single PR use ship-pr; for sequential dependent phases use… - **Type:** Skill - **Install:** `agentstack add skill-davidtheproduct-claude-ship-skills-parallel-ship` - **Verified:** Yes — security-reviewed for prompt injection and unsafe behavior - **Seller:** [davidtheproduct](https://agentstack.voostack.com/s/davidtheproduct) - **Installs:** 0 - **Category:** [Agent Skills](https://agentstack.voostack.com/c/agent-skills) - **Latest version:** 0.1.0 - **License:** MIT - **Upstream author:** [davidtheproduct](https://github.com/davidtheproduct) - **Source:** https://github.com/davidtheproduct/claude-ship-skills/tree/main/skills/parallel-ship ## Install ```sh agentstack add skill-davidtheproduct-claude-ship-skills-parallel-ship ``` Requires the [AgentStack CLI](https://agentstack.voostack.com/docs/cli). Works with Claude Code, Cursor, and any MCP-compatible agent. ## About # Parallel Ship Coordinate several PR-sized changes at once by launching background agents from the session that did the analysis, keeping high-risk changes (payments, auth, anything that shouldn't self-merge) in the main session. This is the chairperson pattern in its parallel form: the session that did the analysis is the only one holding the verified facts, so it stays in charge - writing complete briefs for disposable worker agents, judging their reports against context only it holds - rather than handing off a lossy summary to fresh sessions. ## When to use - One analysis/design context has produced 3+ shippable changes. - The changes touch **disjoint files** (check before launching; two agents on the same file = merge conflicts). - The spec for each change is concrete enough to write down (file paths, exact behavior, verification commands). If you cannot write the spec, the analysis is not finished - do not launch. When NOT to use: sequential phases where PR N+1 builds on PR N's code (use `epic-ship`), or a single change (use `ship-pr`). ## Workflow 1. **Carve the work into PRs by file/module boundary.** One worktree per PR, all forked from the same base via `bash ~/.claude/skills/ship-pr/scripts/worktree-new.sh ` (never stacked - each agent starts from the remote default branch, not from another agent's branch). 2. **Split by risk, not by size.** - Mechanical/well-specified changes (new components, sweeps, copy, config) -> background agents, cheaper model is fine. - High-risk changes (payments, auth, data-integrity, anything that shouldn't self-merge) -> the MAIN session implements these itself, and they don't auto-merge even on green CI. 3. **Write self-contained agent specs.** Each agent prompt must include: worktree setup (via `ship-pr`'s `worktree-new.sh`, never edit the base checkout directly), exact file targets, any project-specific copy/style rules, verification commands (build/typecheck/test - fresh, not cached), commit message format, and "open PR with a DO NOT MERGE line, do not merge, do not close the worktree, return PR URL + decisions made." 4. **Launch disjoint agents in parallel; implement the risky PRs yourself while they run.** 5. **Review each agent's report against your context** - you hold the verified facts from the analysis pass, so judgment calls the agents made (placement, naming, edge cases) are cheap to check against it. 6. **Preview round:** all PRs sit unmerged with preview links or `gh pr diff`. Relay feedback by resuming the same agents (they keep their worktree and context) rather than starting fresh ones. 7. **Merge in dependency order on the user's go**, `gh pr merge --squash --delete-branch`, then close every worktree via `ship-pr`'s `worktree-close.sh`. ## Coordination tricks (learned the hard way) - **Two parallel PRs need the same new util file:** copy it byte-identical between branches (`git fetch origin && git show origin/: > `), verify `git diff origin/ -- ` is EMPTY. Identical additions merge cleanly in either order; any divergence creates a squash conflict. - **`worktree-close.sh` fails after squash-merging a multi-commit branch** (single-commit branches close fine, since the squash SHA differs from any commit on the branch). Confirm `gh pr view --json state` says MERGED, then `WORKTREE_FORCE=1 bash ~/.claude/skills/ship-pr/scripts/worktree-close.sh `. - **Write deliverable files (briefs, docs, reports) inside a worktree from the start**, not the base checkout. An untracked copy sitting in the base checkout blocks the next pull once that file merges via PR. - **Third-party services with production-only credentials** (payment providers, etc.) often can't be tested against a staging/preview environment lacking those secrets. Pin those calls to production explicitly and note it in the PR description rather than discovering a silent 500 in preview. - Post a brief status line as each PR opens; agents' reports aren't visible to the user unless you relay them. ## Related - `ship-pr` - the single-PR workflow each agent follows internally, including branch prefixes and the verify step - `epic-ship` - the sequential counterpart: one PR per phase when each phase builds on the last ## Source & license This open-source skill is cataloged on AgentStack and links to its original source — we do not rehost the code. - **Author:** [davidtheproduct](https://github.com/davidtheproduct) - **Source:** [davidtheproduct/claude-ship-skills](https://github.com/davidtheproduct/claude-ship-skills) - **License:** MIT Install and usage instructions live in the source repository linked above. ## Pricing - **Free** — Free ## Security capabilities Automated source analysis of v0.1.0 — what this tool can access: - **Network access:** no - **Filesystem access:** no - **Shell / process execution:** no - **Environment & secrets:** no - **Dynamic code execution:** no *"Yes" means the capability is present in the source — more access means more to trust, not that it is unsafe.* ## Versions - **0.1.0** — security scan: passed — Imported from the upstream source. ## Links - Listing page: https://agentstack.voostack.com/l/skill-davidtheproduct-claude-ship-skills-parallel-ship - Seller: https://agentstack.voostack.com/s/davidtheproduct - Browse the marketplace: https://agentstack.voostack.com/browse --- Listed on AgentStack — the marketplace for AI agent skills and MCP servers. Every listing is security-reviewed. Creators keep 70%.