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Nodes

MCP Node

Invoke a tool on an attached Model Context Protocol server via JSON-RPC 2.0.

MCP Node

The mcp node calls a tool exposed by an MCP-compatible server using the JSON-RPC 2.0 tools/call method.

Configuration Fields

FieldTypeDefaultDescription
mcpServerIdstring—ID of a pre-configured MCP server in workspace settings (used to resolve the URL and token)
mcpServerUrlstring—Direct URL of the MCP server (used if mcpServerId is not set)
mcpActionstring—Tool name to call (maps to params.name in the JSON-RPC request)
mcpParamsobject | string{}Arguments passed to the tool. Can be a JSON string or an object.
outputFieldfull | text | json | markdownfullHow to extract the result from the server response
accessTokenstring—Bearer token sent as Authorization header (overridden by server config)

Wire Protocol

The node sends a standard MCP tools/call request:

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "<mcpAction>",
    "arguments": { ...mcpParams }
  }
}

Timeout: 30 seconds.

Output Extraction

outputFieldReturns
fullThe entire result from the JSON-RPC response
textFirst text-type content block, or JSON.stringify(result)
markdownresult.markdown, falling back to text extraction
jsonresult.json or result.data, falling back to result

MCP servers must be registered under Settings → Integrations → MCP Servers in your workspace before they can be referenced by mcpServerId. The server URL and token are stored there and resolved at execution time.

Example Config

{
  "mcpServerId": "my-firecrawl-server",
  "mcpAction": "scrape",
  "mcpParams": {
    "url": "{{input.targetUrl}}",
    "formats": ["markdown"]
  },
  "outputField": "text"
}

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