GUI – Live Agent Output Panel

[maddes8cht]

Summary

Currently, agent output is invisible in the GUI. The Execution Log only shows engine lifecycle messages ([OpenLoop] Loaded workflow..., [OpenLoop] State updated: ...).

Add a dedicated output panel or tab in the Tkinter GUI that displays the full agent stdout/stderr in real time during execution.

Design Considerations

Receiver Pattern (recommended)

The ExecutionEngine already supports a logger callback. Extend this to an output_callback that is called with each chunk of agent output:

engine = ExecutionEngine(
    logger=log_queue.put,
    output_callback=output_queue.put,  # new
)

The GUI polls the output queue in _poll_log_queue() and appends text to a read-only Text widget in a dedicated frame/tab.

UI Layout Options

1. Split pane – Execution Log on top, Agent Output on bottom (split via panedwindow)
2. Tabbed – Existing "Execution Log" + new "Agent Output" tab via ttk.Notebook
3. Expandable – Output in a ScrolledText with Show/Hide toggle

Concerns

• Thread safety: Tkinter is not thread-safe. All widget updates must happen on the main thread via the queue polling pattern (already used for the log).
• Performance: Agents can produce very long output (>100k chars). The Text widget should use insert with END and auto-scroll to bottom, with an optional "Auto-scroll" toggle.
• Memory: The Text widget keeps all history. For long workflows, a cap (e.g. last 10k lines) may be needed later.

Priority

Low – File Logging (Issue #24) and CLI Verbose (Issue #25) cover 90% of the need. GUI Output Panel is a nice-to-have for interactive users.