http_server

The http_server block enables the built-in HTTP server. It is optional. If omitted, the agent runs as a process without an HTTP interface.

http_server {
  host = runtime("HTTP_HOST", "127.0.0.1")
  port = runtime("HTTP_PORT", 8080)
  max_request_size = runtime("HTTP_MAX_REQUEST_SIZE", 2097152)

  protocol {
    ag_ui {}
    a2a {}
  }
}

Fields

protocol block

The protocol block enables specific protocol implementations on the HTTP server. Supported protocols are ag_ui and a2a.

ag_ui

protocol {
  ag_ui {
    path = "/ag-ui"
  }
}

Enabling ag_ui mounts the AG-UI streaming protocol on the server. This allows frontend UIs and clients to connect to the agent and receive real-time execution events as a Server-Sent Events stream.

See AG-UI for the full protocol documentation, event types, and client connection examples.

a2a

protocol {
  a2a {
    path = "/a2a"
  }
}

Enabling a2a mounts the foundational Agent2Agent protocol surface on the server. This allows upstream agents to discover the agent, send work as tasks, stream basic task updates, inspect a known task, and cancel a task.

This setting exposes the current agent as an inbound A2A server. To let the current agent call another A2A server, configure an A2A tool with tool { kind = "a2a" }.

See A2A for the supported endpoint shapes and current implementation scope. See Connect agents via A2A for outbound A2A tools.