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Node Introspection

Talos can list ROS 2 nodes through the agent.

The agent uses ROS 2 graph APIs to discover node names, namespaces, publishers, subscribers, and services. Clients request this data with ListNodes.

CLI

talos-cli list-nodes

TUI

The Nodes tab shows discovered nodes on the left. Selecting a node displays its namespace, publishers, subscribers, and services.

Logger Levels

Talos can show and set a node’s logger level through the node’s <node>/get_logger_levels and <node>/set_logger_levels services (rcl_interfaces/srv/GetLoggerLevels and SetLoggerLevels). Nodes only serve these when they opt in:

  • rclcpp: rclcpp::NodeOptions().enable_logger_service(true)
  • rclpy: Node(..., enable_logger_service=True)

Otherwise the agent reports that the logger services are not available.

Requests default to the node’s own logger, whose name is the fully-qualified node name without the leading / and with / replaced by . (/ns/foo is ns.foo). Levels are UNSET (0, inherit the default), DEBUG (10), INFO (20), WARN (30), ERROR (40) and FATAL (50).

Use talos-cli log-level <node> [level], or l / L on the TUI Nodes tab.

Limits

Node introspection reflects the ROS 2 graph state visible to the agent. Network or ROS domain configuration issues outside Talos can affect what the agent sees.