Context limit handling and compression freeze issues

Fixes on record

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

• #55926 fix(compressor): skip compression during summary LLM cooldown to prevent CLI freeze

  merged to main

  files: agent/context_compressor.py, tests/run_agent/test_infinite_compaction_loop.py

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  • agent/context_compressor.py

    @@ -1073,6 +1073,23 @@ def should_compress(self, prompt_tokens: int = None) -> bool:
             tokens = [redacted:secret-assignment] if prompt_tokens is not None else self.last_prompt_tokens
             if tokens < self.threshold_tokens:
                 return False
    +        # Do not trigger compression while the summary LLM is in cooldown.
    +        # On a 429/transient failure _generate_summary() sets a cooldown and
    +        # returns None; compress() then inserts a static fallback marker and
    +        # returns. Tokens stay above threshold, so without this guard every
    +        # subsequent turn re-fires _compress_context() — re-inserting the
    +        # marker and re-entering the loop, making the CLI appear frozen until
    +        # the cooldown expires (issue #11529). Manual /compress passes
    +        # force=True, which clears this cooldown in compress() before running,
    +        # so it still retries immediately.
    +        _cooldown_remaining = self._summary_failure_cooldown_until - time.monotonic()
    +        if _cooldown_remaining > 0:
    +            if not self.quiet_mode:
    +                logger.debug(
    +                    "Compression deferred — summary LLM in cooldown for %.0fs more",
    +                    _cooldown_remaining,
    +                )
    +            return False
             # Anti-thrashing: back off if recent compressions were ineffective
             if self._ineffective_compression_count >= 2:
                 if not self.quiet_mode:

  • tests/run_agent/test_infinite_compaction_loop.py

    @@ -16,6 +16,8 @@
     
     from unittest.mock import patch, MagicMock
     
    +import time
    +
     from agent.context_compressor import ContextCompressor, _CHARS_PER_TOKEN
     
     
    @@ -248,3 +250,36 @@ def test_below_threshold_allows(self):
             comp = _make_compressor(config_context_length=96000)
             comp.last_prompt_tokens = [redacted:secret-assignment]
             assert not comp.should_compress(10_000)
    +
    +
    +# ---------------------------------------------------------------------------
    +# Test: summary-LLM cooldown guard in should_compress (#11529)
    +# ---------------------------------------------------------------------------
    +
    +class TestCooldownGuard:
    +    """should_compress() must skip compression while the summary LLM is in
    +    cooldown, otherwise a 429/transient failure re-fires _compress_context()
    +    every turn (inserting a fallback marker repeatedly) and freezes the CLI.
    +    """
    +
    +    def test_active_cooldown_blocks(self):
    +        """A future cooldown deadline -> should_compress returns False even
    +        when tokens are over threshold."""
    +        comp = _make_compressor(config_context_length=96000)
    +        comp.last_prompt_tokens = [redacted:secret-assignment]
    +        comp._summary_failure_cooldown_until = time.monotonic() + 60
    +        assert not comp.should_compress(65_000)
    +
    +    def test_expired_cooldown_allows(self):
    +        """A past cooldown deadline -> compression resumes normally."""
    +        comp = _make_compressor(config_context_length=96000)
    +        comp.last_prompt_tokens = [redacted:secret-assignment]
    +        comp._summary_failure_cooldown_until = time.monotonic() - 1
    +        assert comp.should_compress(65_000)
    +
    +    def test_no_cooldown_allows(self):
    +        """The default (no cooldown set) does not block compression."""
    +        comp = _make_compressor(config_context_length=96000)
    +        comp.last_prompt_tokens = [redacted:secret-assignment]
    +        assert comp._summary_failure_cooldown_until == 0.0
    +        assert comp.should_compress(65_000)