GitHub Copilot coding agent MCP setup - Sendmux

Use this page to connect Sendmux MCP to your AI client.

Private HTTP

Start a local HTTP MCP server:

SENDMUX_API_KEY=smx_mbx_... \
SENDMUX_MCP_HTTP_BEARER_TOKEN=local-mcp-token \
sendmux-mcp-mailbox --transport http --host 127.0.0.1 --port 8765

Use http://127.0.0.1:8765/mcp as the client URL. Use repository-level MCP settings with a private HTTPS endpoint that the cloud agent can reach. Store the bearer token as an Agents secret or variable whose name starts with COPILOT_MCP_.

{
  "mcpServers": {
    "sendmux": {
      "type": "http",
      "url": "https://your-private-mcp.example.com/mcp",
      "headers": {
        "Authorization": "Bearer $COPILOT_MCP_SENDMUX_MCP_TOKEN"
      },
      "tools": ["*"]
    }
  }
}

GitHub Copilot coding agent does not support remote MCP servers that require OAuth. Do not point it at the hosted Sendmux OAuth endpoint.