ENTERPRISE CRM MODEL CONTEXT PROTOCOL (MCP) RUNTIME
Client-Host-Server JSON-RPC Exchange with OAuth 2.0 PKCE Scoping
1. AI CLIENT / HOST
LLM Agent Runtime
Claude / Custom Agent
TOOL SELECTION LOOP:
1. User asks: "Find VP"
2. Agent checks schema
3. Generates JSON-RPC
4. Evaluates response
Context Window
Contact: ~450 tokens
Company + Deals:
~3,800-5,200 tokens
REQUIRES FIELD PROJECTION
Tool Call (JSON-RPC)
Context Payload
2. REMOTE MCP SERVER
mcp.hubspot.com
Hosted Gateway / Standard API
OAUTH / PKCE BOUNDARY:
✓ crm.objects.contacts.read
✓ crm.objects.deals.read
✕ crm.objects.deals.write
(Human Approval Gate)
Execution Engine
Stateless JSON-RPC protocol.
Translates MCP primitives into
standard REST API calls.
3. SYSTEM OF RECORD
Enterprise CRM
Database Tables & Logs
Contacts
150+ properties
Deals & Quotes
Pipeline state & MRR
Audit Trails
Activity Timeline
GOVERNED STATE