Name: Liate
Author: Liate

How Liate connects to MCP tool servers using Stdio, SSE, and Streamable HTTP transports.

The T-Pillar of liate.json connects your agent to any Model Context Protocol (MCP) tool server. Liate natively supports all 3 MCP transport types — no plugins or extensions needed.

Once connected, Liate calls tools/list to discover available tools and registers them with the LLM. During the ReAct loop, when the LLM emits a tool call, OM automatically executes it and feeds the result back.

The 3 MCP Transports

1. Stdio (Local Binary)

Spawns a child process and communicates via stdin/stdout pipes. Used for local tools like uvx, npx, and compiled executables.

2. SSE (Server-Sent Events)

Connects to a remote MCP server over HTTP event stream. Ideal for SaaS tool gateways like AgentMail.

3. Streamable HTTP

Standard JSON-RPC over HTTPS. Used for MCP servers with REST endpoints that don't require persistent SSE connections.

Stdio Examples (Local Tools)

{
  "T": {
    "time": {
      "command": "uvx",
      "args": ["mcp-server-time"],
      "tools": ["get_current_time"]
    },
    "filesystem": {
      "command": "npx",
      "args": ["-y", "@modelcontextprotocol/server-filesystem", "./workspace"],
      "tools": ["*"]
    },
    "websearch": {
      "command": "websearch.exe",
      "tools": ["web_search", "news_search"]
    },
    "python_tool": {
      "command": "python",
      "args": ["my_mcp_server.py"],
      "tools": ["*"]
    }
  }
}

Windows Note: Liate auto-converts npx → npx.cmd on Windows. No manual adjustment needed.

SSE Examples (Remote Services)

{
  "T": {
    "email": {
      "command": "sse",
      "url": "https://mcp.agentmail.to/sse?apiKey=am_us_inbox_your_key",
      "tools": ["list_inboxes", "list_messages", "send_email"]
    },
    "github": {
      "command": "sse",
      "url": "https://api.githubcopilot.com/mcp/sse",
      "tools": ["*"]
    }
  }
}

Streamable HTTP Examples

{
  "T": {
    "database": {
      "url": "https://mcp.mydb.com/mcp",
      "tools": ["query", "insert", "update"]
    },
    "payments": {
      "url": "https://mcp.razorpay.com/v1/mcp",
      "tools": ["create_payment_link", "check_payment_status"]
    }
  }
}

Tool Filtering

Use tools to whitelist only the tools your agent needs. This reduces system prompt tokens and prevents the LLM from calling irrelevant tools.

"tools": ["*"]                           // Expose all tools
"tools": ["get_current_time"]            // Only this one tool
"tools": ["web_search", "news_search"]   // Two specific tools

Tool Approval Gate

For sensitive tools (payments, email sending, file deletion), you can require human approval before each call. The approval is handled via WebSocket — the UI prompts the user before Liate executes.

{
  "E": {
    "REQUIRE_APPROVAL": "true",
    "AUTO_APPROVE_TOOLS": "get_current_time,web_search"
  }
}

LLM requests tool → Liate checks E.REQUIRE_APPROVAL
  ├── Tool in AUTO_APPROVE_TOOLS → Execute immediately
  └── Tool not in list → WebSocket: { type: "tool_approval_request", tool: "send_email" }
        ├── User approves → Execute tool → Continue
        └── User denies  → "Tool execution denied" → LLM tries alternative

Real-World Agent Examples

Email Agent (AgentMail SSE Gateway):

{
  "L": "sarvam/sarvam-105b",
  "A": { "name": "email-agent", "intent": "You are an email assistant. List, read, and send emails on behalf of the user." },
  "T": {
    "agentmail": {
      "command": "sse",
      "url": "https://mcp.agentmail.to/sse?apiKey=$AGENTMAIL_KEY",
      "tools": ["list_inboxes", "list_messages", "send_email"]
    }
  },
  "E": { "SARVAM_API_KEY": "$SARVAM_API_KEY" }
}

Time Agent (Local uvx):

{
  "L": "sarvam/sarvam-105b-conversations",
  "A": {
    "name": "time-agent",
    "intent": "You are a time analyst. Always use Asia/Kolkata timezone for Indian time.",
    "skills": "./skills.md"
  },
  "T": {
    "time": { "command": "uvx", "args": ["mcp-server-time"], "tools": ["get_current_time"] }
  },
  "E": { "SARVAM_API_KEY": "$SARVAM_API_KEY" }
}

MCP Tools (T-Pillar)