Hamster

Install Hamster. One plugin. Talk through hosted MCP or the CLI. Keep the plan on disk, then ship from it.

This is the Hamster product: Agent Plugins skills on every supported client, hosted MCP on every client that supports MCP and installs from GitHub or a marketplace, plus generated native execution workers on Claude Code, GitHub Copilot CLI, and Grok Build. The CLI is how the plan stays in this repo. It is not a second install.

Install

Installation differs by client. If you use more than one, install Hamster separately for each one.

Cursor

1. Customize → Add Marketplace → Import from GitHub.
2. Paste https://github.com/gethamster/plugin at User scope and select Import.
3. Open the Personal tab and select Add next to Hamster.

On Enterprise, an admin must allow marketplace imports. Once Hamster is on the Cursor marketplace, /add-plugin hamster works too:

/add-plugin hamster

Grok Bot is not a separate Hamster package. It uses the same Cursor account and plugin library, so the Cursor install above is the Grok Bot install. Do not run /add-plugin in the Grok Bot chat. If Grok Bot shows "Complete GitHub auth to sync installed plugins", complete GitHub auth when Grok Bot asks.

Claude Code

/plugin marketplace add gethamster/plugin
/plugin install hamster@hamster-plugins

Codex CLI

codex plugin marketplace add gethamster/plugin
codex plugin add hamster@hamster-plugins

You can also launch codex, run /plugins, and install hamster@hamster-plugins.

Codex Plugins Directory

The Hamster listing in Codex's Plugins Directory is a skills-only build of this same skills tree, produced by node scripts/build-codex-skills-bundle.mjs. A directory install carries the skills and nothing else, so it does not register the hosted MCP connector: Ask Hamster answers through hamster chat there unless you add the connector yourself, as described in Advanced: hosted MCP without the plugin. The GitHub and marketplace installs above are unaffected and keep the connector.

Antigravity

From this repository:

agy plugin install .

Or from GitHub:

agy plugin install https://github.com/gethamster/plugin

If Hamster 3.2 is already installed, uninstall it before you install 3.4. An in-place Antigravity install retains the four skill directories renamed in 3.4.

agy plugin uninstall hamster
agy plugin install https://github.com/gethamster/plugin

In the Antigravity app (2.15 or newer), authenticate hamster_hamster under Settings → Customizations → Installed MCP Servers. The plugin registers that server itself, so a manual hamster entry in mcp_config.json would add a second copy of every tool.

Using GitHub Copilot CLI, Grok Build, or Pi? See More install options.

More install options

GitHub Copilot CLI

copilot plugin marketplace add gethamster/plugin
copilot plugin install hamster@hamster-plugins

To sign in to the hosted MCP server, run /mcp auth hamster.

Grok Build

grok plugin install gethamster/plugin --trust

To sign in to the hosted MCP server, open /mcps, select hamster, and press i.

Pi

pi install git:github.com/gethamster/plugin

Pi has no MCP support, so Hamster runs through the CLI. Run /skill:setup to install it and sign in.

After install

1. Talk — hosted MCP at https://tryhamster.com/mcp, or hamster chat when MCP tools are unavailable and the CLI is signed in. Your client owns the Hamster sign-in.
2. Plan on disk — say Install Hamster, or run ship. The setup skill installs the CLI if needed, runs hamster auth login, and syncs the plan.
3. Ship — execute the brief already on disk. Nothing runs automatically on session start.

Skills

Claude Code and Copilot CLI list these as /hamster:<skill>. Cursor and Grok Build list them as /<skill>, and Pi as /skill:<skill>. The table uses the Claude form.

Four skills carry a -hamster suffix because Cursor invokes plugin skills as a bare /skill-name, and ask, plan, and resume are Cursor's own concepts — cursor-agent --mode takes plan and ask, --resume selects a session — so short names compete with them there. review is renamed with that family so Cursor's command list stays one convention. Claude Code namespaces plugin skills as /<plugin>:<skill> and they cannot conflict, so on Claude the suffix is redundant and you type /hamster:ask-hamster. One skills tree serves every client, so that is the cost of being unambiguous on Cursor. ship, qa, retro, and setup shadow nothing and stay short.

/hamster:setup

The readiness path. Noninteractive check first (ensure-ready). If the CLI is installed and you are signed in, it runs hamster sync to refresh the plan. Otherwise it installs the CLI, opens login, and inits/syncs — only when you asked.

/hamster:ask-hamster

The direct gateway to Hamster's connected workspace context. Uses the Hamster MCP tools when the client has them; otherwise hamster chat is the same ask path over the CLI. Explicit requests can also perform supported workspace actions:

/hamster:ask-hamster I'm modifying auth middleware in apps/web/app/api/. What does our blueprint say about third-party integrations?
/hamster:ask-hamster I prototyped rate limiting in apps/api/middleware/rate-limit.ts. Create a brief for this work.

Follow-up questions continue the same Hamster conversation when they depend on the previous response.

/hamster:ship

The main orchestrator. Accepts a brief slug, UUID, or Hamster Studio URL:

/hamster:ship user-authentication
/hamster:ship https://tryhamster.com/home/hamster/briefs/2de8d546-50ab-4dbd-a678-579ec8119f60

If no argument is given, presents an interactive picker of actionable briefs.

Flow: Readiness (setup/ensure-ready) → Setup (prereqs + live sync) → Brief selection → Inline wave scheduling (one confirmation) → Branch + merge base → Parallel wave execution (implement → validate + test → wave review → bisectable commits) → Final validation → Ask about PR creation

No plan generation or task elaboration occurs at any step — scheduling only organizes the pre-generated tasks into parallel waves.

/hamster:plan-hamster

Read-only analysis with optional deep review. Produces the execution plan without making changes.

/hamster:plan-hamster api-rate-limiting

After analysis, choose a review mode:

• CEO Review (Founder Mode) — 10-section deep dive from first principles
• Eng Review (Architecture Mode) — 4-section technical review with ASCII diagrams and test plan
• Quick Analysis — Just the plan

/hamster:resume-hamster

Resumes an interrupted execution. Auto-detects the brief from the git branch name (feature/{key}-{id}-{slug}), in-progress tasks, or a provided argument.

/hamster:resume-hamster
/hamster:resume-hamster user-authentication

/hamster:review-hamster

Paranoid two-pass code review for the current feature branch:

• Pass 1 (CRITICAL): SQL safety, race conditions, auth boundaries, enum completeness, secrets
• Pass 2 (INFORMATIONAL): Side effects, magic numbers, dead code, test gaps, type coercion, time safety
• Interactive resolution for critical findings with fix/acknowledge/false-positive options

/hamster:review-hamster

/hamster:qa

Systematic testing with 4 modes:

/hamster:qa diff        # Test only what changed (default on feature branches)
/hamster:qa full        # Full test suite with coverage
/hamster:qa quick       # 30-second lint + typecheck + smoke tests
/hamster:qa regression  # Changed files + dependents, flag new failures

Includes issue taxonomy (functional/type-safety/integration/performance/coverage-gap) and optional fix loop.

/hamster:retro

Engineering retrospective from git history:

/hamster:retro          # Last 7 days (default)
/hamster:retro 14       # Last 14 days
/hamster:retro 30       # Last 30 days
/hamster:retro 24h      # Last 24 hours

Produces: metrics table, hourly distribution, session analysis, hotspots, PR sizes, per-contributor deep dive with praise and growth suggestions, trends vs last retro, and a narrative summary.

Execution workers