MCP servers

Covers mcp__mcp-manager__install_mcp_server — registering a new MCP server in Cherry and binding it to the current agent.

Get exact argument shapes from the live tool schema — this reference gives routing, sequencing, and safety only.

Availability

Present for agents that compose with the user's environment. Absent for sealed built-in agents (Cherry Support), where registering servers is not available this session.

Approval

mcp__mcp-manager__install_mcp_server mutates durable state and is approval-gated. For a stdio server the config you pass is a local command line: command + args launch a real process on the user's machine with the env you supply. Install only once the user has signaled intent; if approval is declined, stop and report — don't register the server by editing settings files or shelling out.

Never invent a config

Unlike a skill's opaque install_source, here you author the whole config — so a hallucinated package name or endpoint becomes a real command or a real request. Install only a config the user pasted, linked, or explicitly confirmed. If you are working from a server's documentation, show the user the exact config you are about to register and get confirmation first. Never guess a command, an args package name, or a baseUrl.

env and headers typically carry API keys. Take them from the user; never fabricate a placeholder and never echo a secret back in full.

Workflow

1. Get the config from the user — stdio (local process) needs command; sse and streamableHttp (remote) need baseUrl. name is required for all three.
2. Confirm, then call with activate omitted. The server is registered inactive and untrusted, bound to this agent, for the user to enable in Settings → MCP.
3. Only if the user explicitly asks to turn it on now, pass activate: true — that marks it active and trusted and starts it, so its tools appear on the next tool re-list without a restart.

Report which of the two happened. A registered-but-inactive server runs nothing yet; telling the user their tools are live when they are not sends them debugging a non-problem.

Recovery

• Tool error result (missing command/baseUrl, rejected field, duplicate name) → read the message and correct that field; don't retry the same arguments, and don't fall back to editing MCP settings by hand.
• Approval declined → stop and report; don't register through another route.

Example

"Add the GitHub MCP server, here's my token: ghp_…"

Confirm the config you'll register (npx -y @modelcontextprotocol/server-github, token in env), then call mcp__mcp-manager__install_mcp_server without activate. Tell the user it's registered and where to enable it — unless they asked you to enable it now, in which case pass activate: true and say it's live.