fix(compression): make manual compression feedback truthful

agent/manual_compression_feedback.py

@@ -0,0 +1,49 @@
+"""User-facing summaries for manual compression commands."""
+
+from __future__ import annotations
+
+from typing import Any, Sequence
+
+
+def summarize_manual_compression(
+    before_messages: Sequence[dict[str, Any]],
+    after_messages: Sequence[dict[str, Any]],
+    before_tokens: int,
+    after_tokens: int,
+) -> dict[str, Any]:
+    """Return consistent user-facing feedback for manual compression."""
+    before_count = len(before_messages)
+    after_count = len(after_messages)
+    noop = list(after_messages) == list(before_messages)
+
+    if noop:
+        headline = f"No changes from compression: {before_count} messages"
+        if after_tokens == before_tokens:
+            token_line = (
+                f"Rough transcript estimate: ~{before_tokens:,} tokens (unchanged)"
+            )
+        else:
+            token_line = (
+                f"Rough transcript estimate: ~{before_tokens:,} → "
+                f"~{after_tokens:,} tokens"
+            )
+    else:
+        headline = f"Compressed: {before_count} → {after_count} messages"
+        token_line = (
+            f"Rough transcript estimate: ~{before_tokens:,} → "
+            f"~{after_tokens:,} tokens"
+        )
+
+    note = None
+    if not noop and after_count < before_count and after_tokens > before_tokens:
+        note = (
+            "Note: fewer messages can still raise this rough transcript estimate "
+            "when compression rewrites the transcript into denser summaries."
+        )
+
+    return {
+        "noop": noop,
+        "headline": headline,
+        "token_line": token_line,
+        "note": note,
+    }

cli.py

@@ -5754,21 +5754,29 @@ def _manual_compress(self):
         original_count = len(self.conversation_history)
         try:
             from agent.model_metadata import estimate_messages_tokens_rough
-            approx_tokens = estimate_messages_tokens_rough(self.conversation_history)
+            from agent.manual_compression_feedback import summarize_manual_compression
+            original_history = list(self.conversation_history)
+            approx_tokens = estimate_messages_tokens_rough(original_history)
             print(f"🗜️  Compressing {original_count} messages (~{approx_tokens:,} tokens)...")
 
-            compressed, new_system = self.agent._compress_context(
-                self.conversation_history,
+            compressed, _ = self.agent._compress_context(
+                original_history,
                 self.agent._cached_system_prompt or "",
                 approx_tokens=approx_tokens,
             )
             self.conversation_history = compressed
-            new_count = len(self.conversation_history)
             new_tokens = estimate_messages_tokens_rough(self.conversation_history)
-            print(
-                f"  ✅ Compressed: {original_count} → {new_count} messages "
-                f"(~{approx_tokens:,} → ~{new_tokens:,} tokens)"
+            summary = summarize_manual_compression(
+                original_history,
+                self.conversation_history,
+                approx_tokens,
+                new_tokens,
             )
+            icon = "🗜️" if summary["noop"] else "✅"
+            print(f"  {icon} {summary['headline']}")
+            print(f"     {summary['token_line']}")
+            if summary["note"]:
+                print(f"     {summary['note']}")
 
         except Exception as e:
             print(f"  ❌ Compression failed: {e}")

gateway/run.py

@@ -5000,6 +5000,7 @@ async def _handle_compress_command(self, event: MessageEvent) -> str:
 
         try:
             from run_agent import AIAgent
+            from agent.manual_compression_feedback import summarize_manual_compression
             from agent.model_metadata import estimate_messages_tokens_rough
 
             runtime_kwargs = _resolve_runtime_agent_kwargs()
@@ -5027,6 +5028,13 @@ async def _handle_compress_command(self, event: MessageEvent) -> str:
             )
             tmp_agent._print_fn = lambda *a, **kw: None
 
+            compressor = tmp_agent.context_compressor
+            compress_start = compressor.protect_first_n
+            compress_start = compressor._align_boundary_forward(msgs, compress_start)
+            compress_end = compressor._find_tail_cut_by_tokens(msgs, compress_start)
+            if compress_start >= compress_end:
+                return "Nothing to compress yet (the transcript is still all protected context)."
+
             loop = asyncio.get_event_loop()
             compressed, _ = await loop.run_in_executor(
                 None,
@@ -5047,13 +5055,17 @@ async def _handle_compress_command(self, event: MessageEvent) -> str:
             self.session_store.update_session(
                 session_entry.session_key, last_prompt_tokens=0
             )
-            new_count = len(compressed)
             new_tokens = estimate_messages_tokens_rough(compressed)
-
-            return (
-                f"🗜️ Compressed: {original_count} → {new_count} messages\n"
-                f"~{approx_tokens:,} → ~{new_tokens:,} tokens"
+            summary = summarize_manual_compression(
+                msgs,
+                compressed,
+                approx_tokens,
+                new_tokens,
             )
+            lines = [f"🗜️ {summary['headline']}", summary["token_line"]]
+            if summary["note"]:
+                lines.append(summary["note"])
+            return "\n".join(lines)
         except Exception as e:
             logger.warning("Manual compress failed: %s", e)
             return f"Compression failed: {e}"

tests/cli/test_manual_compress.py

@@ -0,0 +1,66 @@
+"""Tests for CLI manual compression messaging."""
+
+from unittest.mock import MagicMock, patch
+
+from tests.cli.test_cli_init import _make_cli
+
+
+def _make_history() -> list[dict[str, str]]:
+    return [
+        {"role": "user", "content": "one"},
+        {"role": "assistant", "content": "two"},
+        {"role": "user", "content": "three"},
+        {"role": "assistant", "content": "four"},
+    ]
+
+
+def test_manual_compress_reports_noop_without_success_banner(capsys):
+    shell = _make_cli()
+    history = _make_history()
+    shell.conversation_history = history
+    shell.agent = MagicMock()
+    shell.agent.compression_enabled = True
+    shell.agent._cached_system_prompt = ""
+    shell.agent._compress_context.return_value = (list(history), "")
+
+    def _estimate(messages):
+        assert messages == history
+        return 100
+
+    with patch("agent.model_metadata.estimate_messages_tokens_rough", side_effect=_estimate):
+        shell._manual_compress()
+
+    output = capsys.readouterr().out
+    assert "No changes from compression" in output
+    assert "✅ Compressed" not in output
+    assert "Rough transcript estimate: ~100 tokens (unchanged)" in output
+
+
+def test_manual_compress_explains_when_token_estimate_rises(capsys):
+    shell = _make_cli()
+    history = _make_history()
+    compressed = [
+        history[0],
+        {"role": "assistant", "content": "Dense summary that still counts as more tokens."},
+        history[-1],
+    ]
+    shell.conversation_history = history
+    shell.agent = MagicMock()
+    shell.agent.compression_enabled = True
+    shell.agent._cached_system_prompt = ""
+    shell.agent._compress_context.return_value = (compressed, "")
+
+    def _estimate(messages):
+        if messages == history:
+            return 100
+        if messages == compressed:
+            return 120
+        raise AssertionError(f"unexpected transcript: {messages!r}")
+
+    with patch("agent.model_metadata.estimate_messages_tokens_rough", side_effect=_estimate):
+        shell._manual_compress()
+
+    output = capsys.readouterr().out
+    assert "✅ Compressed: 4 → 3 messages" in output
+    assert "Rough transcript estimate: ~100 → ~120 tokens" in output
+    assert "denser summaries" in output

tests/gateway/test_compress_command.py

@@ -0,0 +1,121 @@
+"""Tests for gateway /compress user-facing messaging."""
+
+from datetime import datetime
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from gateway.config import GatewayConfig, Platform, PlatformConfig
+from gateway.platforms.base import MessageEvent
+from gateway.session import SessionEntry, SessionSource, build_session_key
+
+
+def _make_source() -> SessionSource:
+    return SessionSource(
+        platform=Platform.TELEGRAM,
+        user_id="u1",
+        chat_id="c1",
+        user_name="tester",
+        chat_type="dm",
+    )
+
+
+def _make_event(text: str = "/compress") -> MessageEvent:
+    return MessageEvent(text=text, source=_make_source(), message_id="m1")
+
+
+def _make_history() -> list[dict[str, str]]:
+    return [
+        {"role": "user", "content": "one"},
+        {"role": "assistant", "content": "two"},
+        {"role": "user", "content": "three"},
+        {"role": "assistant", "content": "four"},
+    ]
+
+
+def _make_runner(history: list[dict[str, str]]):
+    from gateway.run import GatewayRunner
+
+    runner = object.__new__(GatewayRunner)
+    runner.config = GatewayConfig(
+        platforms={Platform.TELEGRAM: PlatformConfig(enabled=True, token="***")}
+    )
+    session_entry = SessionEntry(
+        session_key=build_session_key(_make_source()),
+        session_id="sess-1",
+        created_at=datetime.now(),
+        updated_at=datetime.now(),
+        platform=Platform.TELEGRAM,
+        chat_type="dm",
+    )
+    runner.session_store = MagicMock()
+    runner.session_store.get_or_create_session.return_value = session_entry
+    runner.session_store.load_transcript.return_value = history
+    runner.session_store.rewrite_transcript = MagicMock()
+    runner.session_store.update_session = MagicMock()
+    runner.session_store._save = MagicMock()
+    return runner
+
+
+@pytest.mark.asyncio
+async def test_compress_command_reports_noop_without_success_banner():
+    history = _make_history()
+    runner = _make_runner(history)
+    agent_instance = MagicMock()
+    agent_instance.context_compressor.protect_first_n = 0
+    agent_instance.context_compressor._align_boundary_forward.return_value = 0
+    agent_instance.context_compressor._find_tail_cut_by_tokens.return_value = 2
+    agent_instance.session_id = "sess-1"
+    agent_instance._compress_context.return_value = (list(history), "")
+
+    def _estimate(messages):
+        assert messages == history
+        return 100
+
+    with (
+        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
+        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
+        patch("run_agent.AIAgent", return_value=agent_instance),
+        patch("agent.model_metadata.estimate_messages_tokens_rough", side_effect=_estimate),
+    ):
+        result = await runner._handle_compress_command(_make_event())
+
+    assert "No changes from compression" in result
+    assert "Compressed:" not in result
+    assert "Rough transcript estimate: ~100 tokens (unchanged)" in result
+
+
+@pytest.mark.asyncio
+async def test_compress_command_explains_when_token_estimate_rises():
+    history = _make_history()
+    compressed = [
+        history[0],
+        {"role": "assistant", "content": "Dense summary that still counts as more tokens."},
+        history[-1],
+    ]
+    runner = _make_runner(history)
+    agent_instance = MagicMock()
+    agent_instance.context_compressor.protect_first_n = 0
+    agent_instance.context_compressor._align_boundary_forward.return_value = 0
+    agent_instance.context_compressor._find_tail_cut_by_tokens.return_value = 2
+    agent_instance.session_id = "sess-1"
+    agent_instance._compress_context.return_value = (compressed, "")
+
+    def _estimate(messages):
+        if messages == history:
+            return 100
+        if messages == compressed:
+            return 120
+        raise AssertionError(f"unexpected transcript: {messages!r}")
+
+    with (
+        patch("gateway.run._resolve_runtime_agent_kwargs", return_value={"api_key": "test-key"}),
+        patch("gateway.run._resolve_gateway_model", return_value="test-model"),
+        patch("run_agent.AIAgent", return_value=agent_instance),
+        patch("agent.model_metadata.estimate_messages_tokens_rough", side_effect=_estimate),
+    ):
+        result = await runner._handle_compress_command(_make_event())
+
+    assert "Compressed: 4 → 3 messages" in result
+    assert "Rough transcript estimate: ~100 → ~120 tokens" in result
+    assert "denser summaries" in result