parallel-feature-development

A set of methods for splitting a large software feature into separate work streams for multiple developers or AI agents. It includes rules for file ownership, interfaces, branches, and merging.

In plain words
What is it for?
Use it to divide work by directory, module, or layer, define how parts connect, choose an integration approach, and combine the completed changes.
Why use it?
It reduces conflicting edits and unclear responsibilities when several people or agents work on related parts of the same codebase at once.

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/wshobson/agents/parallel-feature-development
Any agent
npx skills add wshobson/agents --skill parallel-feature-development
Clone the repo
git clone --depth 1 https://github.com/wshobson/agents

Made for: Claude Code, Codex.

Per session 105 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,364 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 $0.00105 $0.01364
Opus 5 $0.00053 $0.00682
Sonnet 5 $0.00021 $0.00273
Haiku 4.5 $0.00011 $0.00136

Measured 2d ago against content hash 9d39b7d0f301, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

parallel-feature-development 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 2d ago.

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/agent-teams/skills/parallel-feature-development/SKILL.md · 175 lines

How it starts

The opening of the file, as written. The whole thing — 175 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Parallel Feature Development

Strategies for decomposing features into parallel work streams, establishing file ownership boundaries, avoiding conflicts, and integrating results from multiple implementer agents.

When to Use This Skill

  • Decomposing a feature for parallel implementation
  • Establishing file ownership boundaries between agents
  • Designing interface contracts between parallel work streams
  • Choosing integration strategies (vertical slice vs horizontal layer)
  • Managing branch and merge workflows for parallel development

File Ownership Strategies

By Directory

Assign each implementer ownership of specific directories:

implementer-1: src/components/auth/
implementer-2: src/api/auth/
implementer-3: tests/auth/

Best for: Well-organized codebases with clear directory boundaries.

By Module

Assign ownership of logical modules (which may span directories):

implementer-1: Authentication module (login, register, logout)
implementer-2: Authorization module (roles, permissions, guards)

Best for: Feature-oriented architectures, domain-driven design.

By Layer

Assign ownership of architectural layers:

implementer-1: UI layer (components, styles, layouts)
implementer-2: Business logic layer (services, validators)
implementer-3: Data layer (models, repositories, migrations)

Best for: Traditional MVC/layered architectures.

Conflict Avoidance Rules

The Cardinal Rule

One owner per file. No file should be assigned to multiple implementers.

When Files Must Be Shared

If a file genuinely needs changes from multiple implementers:

  1. Designate a single owner — One implementer owns the file
  2. Other implementers request changes — Message the owner with specific change requests
  3. Owner applies changes sequentially — Prevents merge conflicts
  4. Alternative: Extract interfaces — Create a separate interface file that the non-owner can import without modifying

Interface Contracts

Read the full file on GitHub · 175 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. 2d ago First seen · 175 lines · 105 tokens per session scan A 9d39b7d0f301

Subscribe to this mod's changes

parallel-feature-development is a skill published in the GitHub repository wshobson/agents (39,318 stars, last pushed 2d ago), licensed MIT. It adds 105 tokens to every session and 1,364 once invoked, about $0.0005 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.