gohighlevel-mcp

An MCP (Model Context Protocol) server that exposes GoHighLevel CRM operations as tools an LLM agent can call: search contacts, get a contact record, list appointments, log a note, and create a new lead.

Why this server

I maintain production GoHighLevel sub-accounts, Vapi voice agents, and website chatbots for three real-estate brands as part of my day job. The recurring pattern in that work is: a caller or website visitor talks to an agent, the agent needs to check if they're already a CRM contact, see their history and upcoming appointments, log what happened, and either update or create their record. This server exposes exactly that loop as MCP tools, so any MCP-compatible agent (Claude, an n8n AI agent node, a custom LangChain agent, etc.) can plug straight into a GoHighLevel sub-account.

Related MCP server: serve7-mcp-connectors

Design choices

• Python + FastMCP (mcp.server.fastmcp) — matches the rest of my stack (FastAPI, Python automation scripts) and gives automatic input validation via Pydantic without hand-rolled JSON schemas.

• Mock data backend for this build. I don't have a spare GHL sub-account API key to hand over for an evaluation task, so data_store.py reads/writes a local mock_data.json instead of calling https://services.leadconnectorhq.com. Every method in GHLDataStore is named and shaped after the real GHL v2 endpoint it stands in for (see the docstring at the top of data_store.py), so swapping in an httpx.AsyncClient with a real API key is a same-signature change, not a rewrite.

• Tools, not raw endpoint wrappers. ghl_search_contacts + ghl_get_contact + ghl_list_appointments + ghl_create_note + ghl_create_contact map onto real agent tasks (look someone up, check their history, log the outcome), not a 1:1 dump of every GHL API route.

• Read-only tools are annotated readOnlyHint: true; the two write tools (ghl_create_note, ghl_create_contact) are not, so a permission-gating layer upstream can treat them differently — which matters a lot once an agent is allowed to touch real CRM data.

• Errors are actionable, not stack traces. A lookup on an unknown contact_id returns {"error": ..., "suggestion": "Use ghl_search_contacts to find the correct contact_id."} instead of crashing the agent's turn.

Project structure

gohighlevel-mcp/
├── server.py        # MCP server + tool definitions (FastMCP)
├── data_store.py     # Data access layer (mock JSON now, real GHL API later)
├── mock_data.json    # Sample CRM data: 3 contacts, 2 appointments
├── test_server.py    # End-to-end test: spins up server.py as a real
│                      # stdio subprocess and calls every tool through
│                      # a proper MCP ClientSession
└── requirements.txt

Run it

pip install -r requirements.txt
python server.py                # stdio transport, for local MCP clients
python server.py --http         # streamable HTTP on :8000, for remote clients

Test it

python test_server.py

This launches the server as a real subprocess over stdio, connects a real ClientSession, calls list_tools, then exercises all 5 tools (search → get → list appointments → add note → handle a bad id gracefully → create a new lead) and asserts on the results. Not a mocked client — this is the same protocol path a real agent uses.

What I'd add next

• Swap GHLDataStore for an httpx.AsyncClient-backed version that calls the real GHL API with a Location API key from an env var.

• Pagination cursor support to match GHL's actual cursor-based pagination (this mock uses simple offset/limit for clarity).

• A ghl_update_pipeline_stage tool, since stage changes are the other half of the lead-routing loop I handle day to day.