Connect Claude Code, Cursor, and Codex

Give your coding agent the Briefs, Plans, and Blueprints your team already agreed on.

Overview

Hamster runs a hosted MCP Server at https://tryhamster.com/mcp. Claude Code, Cursor, and Codex connect to it through the Hamster plugin, and you sign in once with OAuth. No API key is involved.

Once connected, your agent can search and read your team's Briefs, Plans, Tasks, documents, notes, Initiatives, Goals, and Context Graph relationships. The plugin's setup skill installs the hamster CLI, which syncs Briefs, Tasks, Blueprints, and Methods into the repository's .hamster/ folder as markdown.

Writes follow your role. If your role can create a Brief or move a Task in the browser, your agent can do the same over MCP. If it can't, neither can the agent. Every call runs as you.

Install

You need a Hamster account. To ship, you also need git and the GitHub CLI (gh).

Open Claude Code, Cursor, or Codex in the repository you want to connect, then paste the prompt or follow your tool's steps.

Other MCP Clients

Any tool that supports MCP's Streamable HTTP transport with OAuth 2.1 can connect, including Windsurf and Antigravity. The tool needs outbound HTTPS access to tryhamster.com. Add the hosted URL to your tool's MCP configuration, usually .mcp.json in the project root:

{
  "mcpServers": {
    "hamster": {
      "type": "http",
      "url": "https://tryhamster.com/mcp"
    }
  }
}

Antigravity's mcp_config.json takes "serverUrl" in place of "url". To connect Codex to only the MCP Server, without the plugin, run codex mcp add hamster --url https://tryhamster.com/mcp, then codex mcp login hamster.

Without the plugin you get the MCP tools, including ask_hamster, but not the plugin skills or the synced .hamster/ files. The Plugin page covers Antigravity, Copilot CLI, Grok Build, and Pi.

What Your Agent Reads

Live, over MCP

Area	Tools
Search	search
Accounts and members	list_accounts, switch_account, list_members
Briefs and workspace questions	list_briefs, get_brief, get_hamster_reply
Tasks and subtasks	list_tasks, get_task, get_next_task, list_subtasks
Plans and documents	get_plan, list_documents, get_document
Notes	list_notes, get_note
Initiatives and Goals	list_initiatives, get_initiative, list_goals, get_goal
Context Graph	search_knowledge_graph, explore_entity, get_neighborhood

Available Tools lists every tool, including the write tools below, with what each one does.

Local, from .hamster/

hamster sync writes your active work into the repository as markdown, beside the code that uses it:

Context	Path
Briefs	.hamster/{account}/briefs/{brief}/brief.md
Tasks	.hamster/{account}/briefs/{brief}/tasks/ham-001-title.md
Blueprints	.hamster/{account}/blueprints/, mirroring your Blueprint library
Methods	.hamster/{account}/methods/{slug}/overview.md

After each sync, the CLI also generates .claude/skills/hamster-project-context/SKILL.md, which tells the agent where that context lives. Done and archived Briefs are left out. Both folders are git-ignored by default. CLI Sync covers one-time and continuous sync.

The plugin's Ship skill works from these files: it reads the Brief's Plan and Tasks, the Blueprints, and the Methods, then works through the Tasks in parallel waves. It asks before any push or pull request.

What Your Agent Can Write

Subject to your account role, your agent can:

• Create and update Briefs, Tasks, subtasks, and Initiatives.
• Create and update notes.
• Update Task status as work moves.
• Link and unlink a pull request on a Brief.
• Archive Initiatives and unlink Briefs from them.
• Generate a Plan for a Brief and trigger delivery.
• Ask Hamster with ask_hamster. Each call runs one Hamster agent turn that, within your permissions, can change workspace data, delete Tasks, and use connected apps. Repeating a call can repeat those changes.

Hosted Delivery

When a Brief is delivered in the cloud by a Cloud Agent, the agent gets a separate, smaller set of tools bound to that one delivery job and its Brief or Task. It can read the Brief, Plan, Tasks, and documents it was given, update Task status, and link the delivery's pull request. It cannot list or read unrelated workspace data. Available Tools lists the hosted delivery scope.

Sign-In and Permissions

• OAuth 2.1 with PKCE. Your tool discovers Hamster's sign-in setup from https://tryhamster.com/.well-known/oauth-protected-resource, registers itself if it needs to, and opens your browser to approve the connection.
• Runs as you. Every call carries your token and your team role. There is no admin key or MCP override, so a Reviewer's agent can read a Brief but not edit it.
• Separate team selection. switch_account picks a team for every MCP client connected as you, not only the current session. The team selected in your browser stays as it is.
• Custom clients. A client that can't register itself can be registered manually in Workspace Settings → MCP integrations.

Troubleshooting

• The browser opens again. Your session expired. Approve the connection again; your MCP configuration stays as it is.
• Your tool doesn't support OAuth discovery. Paste a Hamster access token in the Authorization: Bearer … header instead.
• Plugin skills are missing. Install the Hamster plugin in that tool. An MCP-only connection exposes tools, not skills.
• Ask can't reach the MCP Server. If the CLI is installed and signed in, Ask falls back to hamster chat.

Related

• Plugin
• Plugin Skills
• MCP Getting Started
• Available Tools
• CLI Sync
• Cloud Agents
• Hamster for Claude Code
• Hamster for Cursor
• Hamster for Codex