callback.onPhaseStart(ChatPhaseCallback.PHASE_INTENT, "Analyzing...");
        assertEquals(1, events.size());
        assertEquals("start:intent:Analyzing...", events.get(0));

        // Test onPhaseComplete
        callback.onPhaseComplete(ChatPhaseCallback.PHASE_INTENT);
        assertEquals(2, events.size());
        assertEquals("complete:intent", events.get(1));

        // Test onChunk
        callback.onChunk("test content", false);

        onPhaseStart(phase, message);
    }

    /**
     * Called when a processing phase completes.
     *
     * @param phase the phase name that completed
     */
    void onPhaseComplete(String phase);

    /**
     * Called when a chunk of the response is available during streaming.
     *
     * @param content the content chunk
     * @param done true if this is the final chunk
     */