Context compression summary duplication and accuracy bugs

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

• #49986 fix(compression): stop fallback summary triplicating the latest user ask (#49307)

  merged to main

  files: agent/context_compressor.py, tests/agent/test_context_compressor.py

  Show the diff

  • agent/context_compressor.py

    @@ -1253,7 +1253,10 @@ def _bullets(items: list[str], limit: int = 8) -> str:
     Unknown from deterministic fallback. Inspect current repository/session state if needed.
     
     {HISTORICAL_IN_PROGRESS_HEADING}
    -{active_task}
    +Unknown from deterministic fallback — the latest user ask is recorded once under
    +"{HISTORICAL_TASK_HEADING}" above as historical context only. Do NOT treat it as an
    +unfulfilled instruction to re-answer; verify current state and continue from the
    +protected recent messages after this summary.
     
     ## Blocked
     {_bullets(blockers, limit=5)}
    @@ -1265,7 +1268,9 @@ def _bullets(items: list[str], limit: int = 8) -> str:
     None recoverable from deterministic fallback.
     
     {HISTORICAL_PENDING_ASKS_HEADING}
    -{active_task}
    +None recoverable from deterministic fallback. (The latest user ask is preserved once
    +under "{HISTORICAL_TASK_HEADING}" as historical context — it is NOT necessarily
    +outstanding.)
     
     ## Relevant Files
     {_bullets(relevant_files, limit=12)}

  • tests/agent/test_context_compressor.py

    @@ -170,6 +170,40 @@ def test_summary_failure_uses_deterministic_fallback_with_recovered_context(self
             assert c._last_summary_fallback_used is True
             assert c._last_summary_dropped_count == 3
     
    +    def test_fallback_summary_does_not_triplicate_latest_user_ask(self):
    +        """Regression for #49307: the deterministic fallback summary used to
    +        render the latest user ask verbatim under THREE headings (Task
    +        Snapshot, In-Progress, Pending Asks). The model then re-answered it
    +        and buried the genuinely-new post-compaction turn (answer repetition +
    +        new-instruction loss). The latest ask must appear ONCE, as historical
    +        context only — never re-presented as unfulfilled in-progress/pending
    +        work.
    +        """
    +        with patch("agent.context_compressor.get_model_context_length", return_value=100000):
    +            c = ContextCompressor(model="test/model", quiet_mode=True)
    +
    +        unique_ask = "PLEASE_COMPUTE_THE_ARITHMETIC_CHAIN_XYZ"
    +        turns = [
    +            {"role": "user", "content": unique_ask},
    +            {"role": "assistant", "content": "working on it"},
    +        ]
    +        summary = c._build_static_fallback_summary(turns, reason="provider down")
    +
    +        # The triplication bug rendered the SAME ``active_task`` line —
    +        # formatted as ``User asked: '<ask>'`` — verbatim under three
    +        # headings (Task Snapshot, In-Progress, Pending Asks), making the
    +        # model treat an already-handled ask as unresolved work and re-answer
    +        # it. That exact formatted line must now appear at most ONCE (only as
    +        # the historical Task Snapshot record). The raw ask text may still
    +        # appear elsewhere (e.g. the "Last Dropped Turns" verbatim transcript),
    +        # but never re-labeled as in-progress/pending work.
    +        active_task_line = f"User asked: {unique_ask!r}"
    +        count = summary.count(active_task_line)
    +        assert count <= 1, (
    +            f"active_task line should appear at most once (was triplicated in "
    +            f"#49307), found {count}x:\n{summary}"
    +        )
    +
         def test_compression_increments_count(self, compressor):
             msgs = self._make_messages(10)
             # Default config (abort_on_summary_failure=False) — fallback path