MCP

The container also exposes MCP Streamable HTTP at http://127.0.0.1:8080/mcp, on the same port as the HTTP API. It shares the decision service, public model aliases, request validation, body limit, Bearer authentication, and request ID rules with the TypeSafe-compatible HTTP endpoints. Local models use the provider supervisor; hosted Jev does not. The server answers with plain JSON responses rather than an SSE stream.

Connect a client

MCP clients differ in configuration syntax, but they need one Streamable HTTP server URL and the same optional Bearer header:

{
  "mcpServers": {
    "decidealot": {
      "url": "http://127.0.0.1:8080/mcp",
      "headers": {
        "Authorization": "Bearer your-token-here"
      }
    }
  }
}

When authentication is disabled, omit headers. When it is enabled, an absent or wrong token gets the normal HTTP 401 envelope before an MCP session starts. MCP clients perform initialization and retain the Mcp-Session-Id. A client that only supports local stdio can use the OpenClaw bridge described in Agent integrations.

Tools

Tool	Input	Structured output
system_one	Required model, state, and questions, plus optional config, exactly as described in Make decisions.	The same model, answers, and usage object returned by POST /v1/systemone.
system_one_batch	Required nonempty requests list of complete model, state, and questions objects, each with its own optional config.	The same ordered { "results": [...] } object returned by POST /v1/systemone/batch.
list_models	None.	The same { "models": [...] } catalog returned by GET /v1/models.
unload_models	None.	The same unload status and provider list returned by POST /v1/models/unload.

For a system_one call, use this MCP tool argument shape. The questions value has the same choice, score, and noul rules as the HTTP endpoint.

{
  "model": "laya-typed-decisions",
  "state": {
    "operation": "delete",
    "reversible": false
  },
  "questions": {
    "handling": {
      "type": "choice",
      "criteria": {
        "allow": "The operation is reversible and authorized.",
        "review": "A human must review the operation first."
      }
    }
  }
}

Call list_models and unload_models with an empty argument object, {}. The tools return structured output matching the HTTP result bodies, so an agent can inspect probabilities before it chooses the next action.

Errors

MCP tool validation, unknown model, provider busy, and provider unavailable failures return isError: true. A validation error includes the TypeSafe {"detail":[...]} body in its text content. Other failures carry the same message the HTTP API returns, such as the selected provider is unavailable. No tool accepts a provider URL, executable, filesystem path, model directory, or arbitrary runtime option.

Expose MCP through a proxy

The MCP server keeps DNS rebinding protection enabled. Loopback clients and containers using the decidealot Docker service name work by default. A proxy, tunnel, or public DNS name must be allowed explicitly. Add the exact public Host value to DECIDEALOT_MCP_ALLOWED_HOSTS. Browser-based MCP clients must also add their exact origin, including the scheme, to DECIDEALOT_MCP_ALLOWED_ORIGINS.

For a proxy that publishes https://mcp.example.net/mcp, put these values in the Compose .env file before docker compose up -d, or pass the same variables with docker run --env:

DECIDEALOT_API_KEY=replace-with-a-real-secret
DECIDEALOT_MCP_ALLOWED_HOSTS=127.0.0.1,127.0.0.1:*,localhost,localhost:*,[::1],[::1]:*,decidealot,decidealot:*,mcp.example.net
DECIDEALOT_MCP_ALLOWED_ORIGINS=http://127.0.0.1:*,http://localhost:*,http://[::1]:*,https://mcp.example.net

Setting either variable replaces its default, so keep the loopback entries in the list. Keep --publish 127.0.0.1:8080:8080 when a local reverse proxy terminates TLS. The proxy forwards the request unchanged with Host: mcp.example.net. Invalid or missing bearer credentials return 401 first. After bearer authentication, Decidealot returns 421 for an untrusted host and 403 for an untrusted browser origin. Do not disable this protection or allow a broad wildcard for an internet-facing endpoint.