arn-code-batch-implement

A workflow for sending several feature implementations to separate coding agents working in isolated Git worktrees.

In plain words
What is it for?
Use it to implement a group of features in parallel and pass the completed work to a later merge step.
Why use it?
It lets multiple features be built at the same time while keeping their changes separate and tracking each worker's progress.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/appsvortex/arness/arn-code-batch-implement
Any agent
npx skills add AppsVortex/arness --skill arn-code-batch-implement
Clone the repo
git clone --depth 1 https://github.com/AppsVortex/arness

Made for: Claude Code, Codex.

Per session 123 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,739 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00123 $0.03739
Opus 5 $0.00062 $0.01869
Sonnet 5 $0.00025 $0.00748
Haiku 4.5 $0.00012 $0.00374

Measured yesterday against content hash 04fbb648fb6b, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

arn-code-batch-implement scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

plugins/arn-code/skills/arn-code-batch-implement/SKILL.md · 247 lines

How it starts

The opening of the file, as written. The whole thing — 247 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Arness Batch Implement

Orchestrate parallel worktree-isolated background agents to implement multiple features simultaneously. Each worker is a full independent session with all tools, operating in its own git worktree. The orchestrator (this skill) handles pre-flight validation, worker spawning, progress tracking, and handoff to batch-merge.

Key architectural constraint: This skill is a sequencer — it MUST NOT duplicate sub-skill logic. Workers handle all implementation details autonomously.

Pipeline position:

arn-code-batch-planning -> **arn-code-batch-implement** (pre-flight -> spawn workers -> track -> handoff) -> arn-code-batch-merge

Workflow

Step 0: Ensure Configuration

Read ${CLAUDE_PLUGIN_ROOT}/skills/arn-code-ensure-config/references/step-0-fast-path.md and follow its instructions. Extract from ## Arness:

  • Plans directory -- base path where project plans are saved
  • Code patterns -- path to the directory containing stored pattern documentation
  • Template path -- path to the report template set (JSON templates)

Step 1: Pre-flight Validation

Read ${CLAUDE_PLUGIN_ROOT}/skills/arn-code-batch-implement/references/preflight-validation.md and follow its procedure. The preflight reference handles scanning and returns a structured result. Based on that result:

If zero pending plans found: inform the user: "No pending plans found. Run /arn-code-batch-planning to plan features first." Exit.

If Git is no in ## Arness: "Batch implementation requires git for worktree-based parallel execution. Run /arn-implementing to implement features one at a time instead." STOP.

If gh/bkt auth not available (based on Platform): warn that PRs cannot be created — workers will commit but skip PR creation.

If uncommitted changes detected: warn and suggest committing first. Ask (using AskUserQuestion):

Uncommitted changes detected. Commit or stash before launching batch?

  1. Proceed anyway
  2. Cancel — I'll commit first

Read the full file on GitHub · 247 lines

Files

What ships with it

2 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 247 lines · 123 tokens per session scan A 04fbb648fb6b

Subscribe to this mod's changes

arn-code-batch-implement is a skill published in the GitHub repository AppsVortex/arness (33 stars, last pushed 1mo ago), licensed MIT. It adds 123 tokens to every session and 3,739 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.