Connect an MCP server

Connect an existing Model Context Protocol (MCP) server to discover the tools it exposes. You can then attach selected tools to agents without copying their implementations into SLNG.

Prerequisites

An MCP server reachable over Streamable HTTP or server-sent events (SSE).
Its URL and authentication requirements.
Permission to manage organization MCP servers, tools, and Vault secrets.

Add the server

Dashboard
API

Open Global Tools, select the MCPs tab, and choose Add MCP server.

The MCPs tab with Add MCP server highlighted — Open the MCPs tab and add a server

Enter a name, server URL template, and optional description. Select HTTP streaming unless the server requires SSE.

The Add MCP server form with Server URL template highlighted — Configure the MCP server endpoint and transport

Create the connection configuration. This example creates the bearer secret in the Vault with the same request. Replace <MCP_BEARER_TOKEN> before sending it.

server.json

{
  "name": "Wayne inventory",
  "description": "Inventory tools for Wayne Enterprises support agents.",
  "url_template": "https://mcp.wayne.example/mcp",
  "transport": "streamable_http",
  "auth": {
    "type": "bearer",
    "secret_name": "WAYNE_MCP_TOKEN"
  },
  "headers": [],
  "credentials": [
    {
      "mode": "create",
      "secret_name": "WAYNE_MCP_TOKEN",
      "value": "<MCP_BEARER_TOKEN>"
    }
  ]
}

Request

curl -X POST https://api.agents.slng.ai/v1/agents/mcp-servers \
  -H "Authorization: Bearer $SLNG_API_KEY" \
  -H "Content-Type: application/json" \
  -d @server.json

Configure authentication

Choose no authentication, bearer authentication, or a custom authentication header. Secret names use SCREAMING_SNAKE_CASE and refer to Vault values.You can also add literal or Vault-backed custom headers. Do not duplicate the configured authentication header or transport-managed headers.

Verify the connection

Dashboard
API

Choose Connect. Confirm that the server status is ready and review the discovered tool names, descriptions, and schemas.

Use the server id returned by the create request.

Request

curl -X POST \
  https://api.agents.slng.ai/v1/agents/mcp-servers/$SERVER_ID/connect \
  -H "Authorization: Bearer $SLNG_API_KEY"

A successful response has status: "connected" and lists discovered tools in capabilities.tools.

Attach an exposed tool

Select a discovered tool and attach it to an agent. The attachment stores the server ID, tool name, and observed schema hash. MCP tools are model-invoked.See Attach a tool to an agent.

Handle unavailable servers

The connection status can be unknown, healthy, unavailable, invalid, or circuit_open. If discovery fails, verify the transport, URL, credentials, and server response before reconnecting. An attached tool remains tied to the schema hash observed during discovery. If the server changes that schema, reconnect and review the attachment before using the new contract. During a call, an unavailable server returns a tool failure to the agent; it does not silently substitute another tool. See MCP servers API reference for the full connection and discovery fields.

Get started

Regions

Execution layer

Agent Builder

Models

Integrate

Prerequisites

Handle unavailable servers

​Prerequisites

​Handle unavailable servers

Prerequisites

Handle unavailable servers