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What is MCP?

MCP (Model Context Protocol) is an open protocol that allows AI agents to connect to external tools and services. Think of it as a universal adapter that lets your agent interact with Gmail, Salesforce, Slack, and any other service.

How MCP Works

  1. Agent receives user request - “Send an email to john@example.com
  2. Agent decides to use a tool - Determines Gmail tool is needed
  3. MCP protocol bridges the connection - Standardized communication
  4. Connector executes the action - Actually sends the email via Gmail API
  5. Result returns to agent - “Email sent successfully”

Key Concepts

Connectors

Connectors are MCP-compatible servers that provide tools to your agent.
// A connector provides tools like:
{
  "name": "gmail",
  "tools": [
    "send_email",
    "read_emails",
    "search_emails",
    "reply_to_email"
  ]
}

Tools

Tools are individual actions your agent can perform through a connector.
// Example: Gmail's send_email tool
{
  "name": "send_email",
  "description": "Send an email message",
  "parameters": {
    "to": "recipient@example.com",
    "subject": "Meeting reminder",
    "body": "Don't forget our 3pm meeting"
  }
}

Tool Calling

When your agent needs to use a tool:
  1. Agent analyzes user request - Understands what action is needed
  2. Agent selects appropriate tool - Chooses “send_email” from Gmail connector
  3. Agent prepares parameters - Extracts to, subject, body from context
  4. MCP executes tool - Connector sends the email
  5. Agent receives result - Uses response to continue conversation

Two Types of Connectors

1. Pre-built Connectors

BoostGPT provides 30+ ready-to-use connectors:
  • Managed by BoostGPT - We handle hosting, updates, and maintenance
  • OAuth authentication - Secure connection to your accounts
  • One-click deployment - Just authenticate and connect
Example: Deploying Gmail
Dashboard -> Integrations -> Connectors -> Gmail -> Deploy
-> Authenticate with Google -> Add to Agent Tools

2. External MCP Servers

Connect any MCP-compatible server from the internet:
  • You provide the URL - Point to any MCP server
  • Third-party or self-hosted - Host your own or use community servers
  • Custom tools - Access specialized tools not in our library
Example: Connecting external server
Agent -> Tools Tab -> Add Tool -> Add New
-> Enter MCP URL: https://mcp.example.com -> Connect

MCP Protocol Flow

// 1. Agent decides to use a tool
User: "Send an email to john@example.com about the meeting"

// 2. Agent makes MCP request
{
  "connector": "gmail",
  "tool": "send_email",
  "parameters": {
    "to": "john@example.com",
    "subject": "Meeting reminder",
    "body": "Don't forget our meeting at 3pm today"
  }
}

// 3. Connector executes via Gmail API
Gmail API.sendEmail({...})

// 4. MCP returns result
{
  "success": true,
  "message_id": "msg_abc123",
  "timestamp": "2025-01-05T15:30:00Z"
}

// 5. Agent responds to user
Agent: "I've sent the email to john@example.com"

Authentication

OAuth Flow (Pre-built Connectors)

1. User clicks "Deploy" on connector
2. Redirected to service (e.g., Google)
3. User grants permissions
4. BoostGPT receives access token
5. Connector can now act on user's behalf

API Key (External Servers)

1. Get API key from MCP server provider
2. Enter URL when connecting to agent
3. Optionally provide API key if required
4. Connector authenticates with external service

Security

Pre-built Connectors

  • OAuth 2.0 - Industry-standard secure authentication
  • Encrypted storage - Tokens encrypted at rest
  • Scoped permissions - Only request necessary permissions
  • Revokable access - Disconnect anytime from Dashboard

External Servers

  • HTTPS required - All MCP servers must use HTTPS
  • You control access - Manage authentication yourself
  • Audit logs - See all tool executions in agent Insights

Real-World Example

Building a Sales Agent

// 1. Deploy connectors
Dashboard -> Integrations -> Connectors:
  - Deploy Salesforce
  - Deploy Gmail
  - Deploy Google Calendar

// 2. Add to agent
Agent -> Tools Tab:
  - Add Salesforce connector
  - Add Gmail connector
  - Add Calendar connector

// 3. Agent can now:
User: "Show me all deals closing this month"
Agent: *uses Salesforce* "Found 8 deals worth $340K..."

User: "Email the sales rep for the biggest deal"
Agent: *uses Salesforce to get contact, Gmail to send* "Emailed Sarah at..."

User: "Schedule a review meeting for next week"
Agent: *uses Calendar* "Meeting scheduled for Jan 12 at 10am"

MCP vs Direct API Integration

FeatureMCP ProtocolDirect API
SetupDeploy connector, add to agentWrite custom code for each API
MaintenanceAutomatic updatesManual updates required
AuthenticationOAuth handled for youImplement OAuth yourself
Agent AccessAutomatic tool callingManual prompt engineering
Multi-serviceOne pattern for allDifferent code per service

Supported Tool Types

MCP connectors can provide various tool types:

Data Access

  • Read data (emails, contacts, files)
  • Search and filter
  • Query databases

Actions

  • Send messages
  • Create records
  • Update information
  • Delete items

Scheduled Tasks

  • Set reminders
  • Schedule events
  • Automate workflows

Real-time

  • Subscribe to events
  • Stream data
  • Webhooks

Building Your Own Connector

Want to create a custom MCP connector? See our guide:

Debugging Tools

Agent Insights

View all tool executions:
Agent -> Insights Tab -> Tool Analytics
- See which tools are called
- View success/failure rates
- Monitor response times

Test in Playground

Agent -> Playground Tab
- Ask agent to use tools
- See real-time tool execution
- Debug parameter passing

Limitations

Rate Limits

Each service has its own rate limits:
  • Gmail: 100 emails/day (free), 2,000/day (Google Workspace)
  • Salesforce: API limits by license tier
  • HubSpot: 100 requests/10 seconds
Your agent automatically respects these limits.

Permissions

Agents can only use tools you’ve connected:
// If only Gmail is connected:
User: "Create a Salesforce contact"
Agent: "I don't have access to Salesforce. Please connect it first."

Connector Availability

By plan:
PlanConnectors
Free1 connector
Starter5 connectors
Pro20 connectors
ScaleUnlimited

Next Steps