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mero-mcpmero-mcpmero-mcp

mero-mcp

Point your AI harness at a Calimero node. mero-mcp exposes contexts, namespaces and blobs as MCP tools, then reads any installed application's ABI and generates one schema-validated tool per method — so the agent calls your app directly, with arguments the node will actually accept.
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Get Started

Register the server with Claude Code, Cursor, Codex CLI or Claude Desktop, then verify the connection against a real node. Set it up →

Guides

Select an application and call its methods, manage the contexts and namespaces those calls run against, and diagnose the failures that actually come up. Browse the guides →

Understand

How the server finds a node, how it authenticates, what that credential can do, and how an ABI becomes a tool list. See the architecture →

Reference

Every tool with its arguments, every environment variable, and the exact ABI-type→JSON-Schema mapping. Open the reference →

What it is

Section titled “What it is”

@calimero-network/mero-mcp is a Model Context Protocol server that speaks stdio — your MCP client spawns it as a subprocess, and it talks to one Calimero node over that node’s HTTP admin API and JSON-RPC.

It registers two kinds of tools:

  • Fixed tools for the node itself — node_status, list_contexts, create_context, install_application, create_namespace and the rest, grouped into toolsets you can trim.
  • Generated tools, one per method of any application you point it at. Run select_app and the server fetches that application’s ABI from the node, turns each method into an MCP tool with a real JSON Schema for its arguments, and registers it for the life of the process.

That second part is the reason this exists. An agent holding kv_store_set(key: string, value: string) with a validated schema does not have to guess at a JSON-RPC envelope, a context id, or an argument shape.

Requirements

Section titled “Requirements”
  • Node.js 20+ — the server is published as an npm package and run with npx.
  • A running Calimero node — the Calimero desktop app or merod directly.
  • An application installed on that node, and a context created for it. Installing an application does not create a context, and most app tools need one. See contexts and namespaces.

The ABI endpoint that generated tools depend on (GET /admin-api/applications/:id/abi) is newer than the current merod release, so until a release carries it you need a merod built from core master.

Section titled “Related”
  • Calimero Core — the node, the protocol, and the Rust SDK.
  • mero-js — the JavaScript client this server drives the node through.
  • Calimero JS SDK — writing the applications this server calls.