Cosmosmith

July 4, 2026 · View on GitHub

Give your AI coding agents a product team, an architecture desk, a task board, and a release gate in one command.

Cosmosmith helps you turn a rough product idea into a governed multi-agent workflow. It initializes project rules, spec templates, task ledgers, editor adapters, and Codex role skills so agents can move from discovery to implementation with verification evidence instead of drifting through prompts.

中文文档 | npm | GitHub

Start In 10 Seconds

npx cosmosmith@latest init --all

You get a project workspace for AI-assisted building:

AGENTS.md                         project constitution for agents
task.md                           claimable task ledger with evidence fields
proposal.md                       product proposal template
design.md                         technical and UX design template
docs/cosmosmith/idea-brief.md      product discovery notes
docs/cosmosmith/research-brief.md  research notes
CLAUDE.md                         Claude Code adapter
.cursor/rules/cosmosmith.mdc       Cursor adapter
.github/copilot-instructions.md    GitHub Copilot adapter
.opencode/AGENTS.md                OpenCode adapter
.trae/rules/cosmosmith.md          Trae adapter

Why Developers Use It

AI agents are fast, but fast code is not the same as a finished product. Cosmosmith gives the work a spine:

  • Clarify the idea before implementation starts.
  • Split responsibilities across product, research, architecture, UX, frontend, backend, QA, DevOps, and governance roles.
  • Publish tasks into task.md so agents claim small pieces instead of wandering.
  • Require evidence before a task can be marked done.
  • Share one rule source across Codex, Claude Code, Cursor, Copilot, OpenCode, and Trae.

The core model is:

Prompt -> Context -> Harness -> Loop
  • Prompt: what the agent is being asked to do.
  • Context: the files, research, constraints, and decisions that matter.
  • Harness: tests, scripts, checks, and release gates.
  • Loop: review, verification, feedback, and rule updates.

CLI Or Plugin

Cosmosmith has two useful layers.

LayerWhat it doesWhen to use
CLI initializerGenerates AGENTS.md, task.md, spec templates, and editor adapters.Use this in any project.
Codex pluginAdds $cosmosmith-* role skills to Codex.Use this when you want Codex to load the role workflows directly.

The CLI works everywhere:

npx cosmosmith init
npx cosmosmith@latest init
npx cosmosmith@latest init --all
npx cosmosmith@latest init --dir ./my-project --all

Useful options:

npx cosmosmith@latest init --claude --cursor --copilot
npx cosmosmith@latest init --opencode --trae
npx cosmosmith@latest init --all --dry-run
npx cosmosmith@latest init --all --force

Existing files are skipped by default. Use --force only when you intentionally want to overwrite generated files.

Codex Plugin Install

Codex users can install the role skills as a native plugin:

codex plugin marketplace add devnomad-byte/cosmosmith
codex plugin add cosmosmith@cosmosmith

Start a new Codex thread after installation so the new skills are loaded.

Role Mesh

Cosmosmith is not just one prompt. It is a working set of roles that hand off artifacts to each other.

SkillWhat it helps the agent do
cosmosmith-product-discoveryTurn a vague idea into users, jobs, first slice, and acceptance criteria.
cosmosmith-market-researchResearch competitors, analogues, standards, risks, and current external facts.
cosmosmith-spec-governorConvert discovery into proposal.md, design.md, and claimable tasks.
cosmosmith-architectDefine boundaries, data flow, reliability, security, and integrations.
cosmosmith-ui-ux-designerDesign flows, screens, interaction states, accessibility, and visual direction.
cosmosmith-frontend-engineerImplement frontend task slices and record verification evidence.
cosmosmith-backend-engineerImplement APIs, domain logic, persistence, permissions, and contracts.
cosmosmith-qa-verifierTurn acceptance criteria into reproducible tests and QA evidence.
cosmosmith-devops-releaseCheck build, CI, deployment, monitoring, rollback, and release readiness.
cosmosmith-governance-reviewFind rule drift, missing evidence, weak handoffs, and incomplete tasks.
cosmosmith-project-rulesGenerate or update project instruction files and editor adapters.

Typical Workflow

rough idea
  -> product discovery
  -> market research when facts may be current
  -> proposal and design
  -> task.md
  -> frontend/backend slices
  -> QA evidence
  -> release readiness
  -> governance review

Example instruction to your agent:

Use Cosmosmith. I want to build a quiet personal CRM for independent consultants.
Start with product discovery, then publish the first task ledger.

Verify Your Install

Create a temporary workspace:

npx cosmosmith@latest init --all --dir .tmp/cosmosmith-check

Check the output:

ls .tmp/cosmosmith-check

You should see AGENTS.md, task.md, proposal.md, design.md, CLAUDE.md, and docs/cosmosmith/.

Development

npm run validate
npm run smoke:init

Validate the Codex plugin manifest:

python path/to/plugin-creator/scripts/validate_plugin.py plugins/cosmosmith

Preview the npm package:

npm pack --dry-run

Roadmap

  • cosmosmith init --sample for a tiny verified demo workflow.
  • Task ledger consistency validator.
  • Better post-init guidance for CLI vs runtime skills.
  • More adapters as agent rule conventions stabilize.

License

MIT