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.
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 (project managers, adversarial reviewers, investigators, architectural analysts, testing and security specialists) to do the judgment-heavy work, 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.
- New to han? → Start with Concepts, then the Quickstart.
- Looking for a specific skill? → Skills Index. 19 skills grouped by purpose.
- Looking for a specific agent? → Agents Index. 22 agents grouped by role.
- Wondering how the agent swarms scale? → Sizing. The small / medium / large dispatch model used by
/architectural-analysis,/code-review,/gap-analysis,/iterative-plan-review,/plan-a-feature,/plan-implementation, and/research. - Wondering why a skill said "YAGNI"? → YAGNI. The evidence-based rule every planning, review, and architecture skill applies before committing items to an artifact.
- Writing or editing a skill or agent? → Contributing.
Add the Test Double skills marketplace to Claude Code, then install the plugin:
/plugin marketplace add testdouble/han
/plugin install han@han
- Concepts. Skill vs. agent, and how they compose. Read once before using the plugin.
- Quickstart. Four paths for four common situations. Each path is a short sequence of skills.
- Skills Index. All 19 skills, grouped by purpose.
- Agents Index. All 22 agents, grouped by role.
- Sizing. The small / medium / large model that decides how many agents the swarming skills dispatch.
- YAGNI. The evidence-based "You Aren't Gonna Need It" rule every planning, review, and architecture skill applies.
- Contributing. Adding or editing skills, agents, and documentation.
- Changelog. What's new in each version of the plugin.
- Maintenance horizon: Indefinitely maintained, best-effort. No SLA.
- Project type: Personal project, with some Test Double support
- How to report issues: GitHub Issues, with expected best effort for response within 2 weeks.
Han is an open source product of Test Double, and maintained by the following people:
- River Lynn Bailey: Creator, and primary maintainer
Copyright 2026 Test Double, Inc. Distributed under the MIT license.