Han: For the Solo Product Engineer

Han is a suite of AI skills and agents for solo (or small-team) product engineers. It combines evidence-based planning, test-driven implementation, full documentation maintenance, deep code review, and architectural analysis into a team of specialists you can dispatch from Claude Code.

What this plugin does

Han turns planning, implementation, review, and documentation work that would normally take a team into a set of deterministic skills you run from Claude Code.

Each skill dispatches specialist agents, such as project managers, adversarial reviewers, investigators, architectural analysts, and testing and security specialists, to do the judgment-heavy work. It then folds their findings into an artifact you can trust.

The skills are designed to compose. You can plan a feature, then plan its implementation, then iterate on the plan, then build it test-first, then review the resulting code, then write the PR description. All through named skills that hand off to each other cleanly.

Read Concepts for the skill-and-agent model that runs through the whole plugin.

For Solo Product Engineers and Small Teams

Han is purpose-built for solo product engineers and small teams, instead of large teams or enterprise. This does not mean it can't work in larger teams, though. Read about why Han's focus is solo product engineers and small teams to understand Han's positioning and what it does not bring to the table.

Installation

Claude Code

Add the Test Double skills marketplace to Claude Code, then install the plugin:

/plugin marketplace add testdouble/han
/plugin install han@han

Han ships as multiple plugins:

Plugin	Type	What it brings
han	parent	the parent plugin that brings in han-communication, han-core, han-documentation, han-research, han-planning, han-coding, han-github, and han-reporting
han-communication	bundled	the foundational plugin beneath every other: the shared readability standard and writing-voice profile, plus the skills and agent that apply them
han-core	bundled	the shared specialist agent roster, the project-discovery skill, the /pairing collaborative working mode, and the canonical rule files
han-documentation	bundled	documentation skills: project docs, architectural decision records, and runbooks
han-research	bundled	pre-planning knowledge-work skills: research, gap analysis, and issue triage, plus the research-analyst agent
han-planning	bundled	planning skills you reach for before implementation
han-coding	bundled	coding skills you reach for while working in code
han-github	bundled	GitHub-facing skills like posting a code review on a PR
han-reporting	bundled	reporting skills like the stakeholder summary
han-feedback	opt-in	skill for capturing post-session feedback on Han skill runs
han-atlassian	opt-in	skills for publishing docs and work items to Atlassian products
han-linear	opt-in	skill for publishing work items to Linear (requires a Linear MCP server)
han-ddd	opt-in	strategic Domain-Driven Design analysis: bounded context discovery and an evidence-backed domain and context map
han-plugin-builder	opt-in	carries the guidance and skills for building your own skills, agents, and plugins

Installing han@han pulls in the bundled suite (the meta-plugin plus han-communication, han-core, han-documentation, han-research, han-planning, han-coding, han-github, and han-reporting), and is the right choice for most people. If you want only one slice of Han, install a single layer such as han-documentation@han or han-coding@han instead (each brings the shared han-core agents along), and add other specific plugins as desired.

For the full picture and a quick "which one do you need?" guide, see Choosing a Han plugin.

Codex

Add this repo as a Codex marketplace:

codex plugin marketplace add testdouble/han

Codex does not yet support meta-plugins like han@han (see openai/codex#23531,) and it resolves no dependencies, so install the Han packages directly — starting with the foundational han-communication, which the prose-producing packages depend on:

codex plugin add han-communication@ha