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fix(providers): suppress idle watchdog during in-flight Copilot tool calls - #490
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…calls The Copilot SDK emits no events between tool.execution_start and tool.execution_complete, so a stale idle clock during a long-running tool call was indistinguishable from a genuinely stuck session, triggering a spurious "please continue" recovery prompt mid tool-call that could overwrite the agent's eventual structured output. In-flight tool calls (tracked by tool_call_id) now suppress idle recovery entirely while any remain outstanding; max_session_seconds / max_agent_iterations remain the backstop for a genuinely wedged tool. last_activity_ref's tool name is cleared (or rolled to another still-in-flight tool) on tool.execution_complete instead of only ever being set. Adds configurable runtime.idle_timeout_seconds and runtime.max_idle_recovery_attempts (Copilot-only) so workflows with legitimately long tool calls can tune the watchdog. Closes#488
…ression Blocking fixes (#488): - Remove the "pop the oldest entry" fallback in the tool.execution_complete handler that could evict a different, still-running tool's active_tools entry on a duplicate/unmatched event, re-arming the watchdog mid-tool-call and reproducing #488 while appearing fixed. Replaced with a non-mutating debug log; max_session_seconds remains the backstop for a stale entry. - Strengthen TestOnEventActiveTools assertions so both tests actually pin the fix (verified to fail against the pre-fix provider, pass post-fix). - Add an end-to-end regression test driving a real tool.execution_start -> silence -> tool.execution_complete sequence through _send_and_wait, asserting the recovery prompt never clobbers response_content. - Add a warn-once latch (mirroring _context_window_anomaly_warned) so the first occurrence of extended idle-recovery suppression during a session is logged at warning level (console + logger), instead of silently degrading a previously console-visible 90s warning into up to 31.5 minutes of total silence. Recommendations applied: - Corrected the repeated false claim that the SDK "emits no events" during a tool call (it does not guarantee any, but tool.execution_progress / tool.execution_partial_result exist and are opt-in) across copilot.py, schema.py, docs/configuration.md, CHANGELOG.md, and the PR description; consolidated the rationale into one canonical docstring. - Corrected the inaccurate claim that max_agent_iterations backstops a wedged tool call (its counter only advances on tool.execution_start, so it's frozen for the whole wedge) — max_session_seconds is the sole backstop. - Added IdleRecoveryConfig.__post_init__ validation so directly-constructed configs (bypassing the Pydantic schema bounds) can't produce an unbounded busy-wait loop. - Simplified factory.py's IdleRecoveryConfig construction to a dict-filter + single constructor call instead of a three-way ternary per field. - Added ProviderCapabilities.idle_recovery (Copilot-only) with a workflow-level validator warning (not an error, since these are tuning knobs rather than safety bounds) when idle_timeout_seconds / max_idle_recovery_attempts are set against a provider that ignores them. - Bounded two previously-unbounded busy-wait test loops with asyncio.wait_for(..., timeout=5.0). - Added an overlapping-tool-calls end-to-end test keyed on tool_call_id (not tool_name), verified to reproduce the hang if the dict were mistakenly keyed by tool name instead. - Documented the max_session_seconds backstop in docs/configuration.md so a legitimately long tool call doesn't silently exceed it unexpectedly. Skipped: ACA forwarding of the two idle-recovery fields (larger, separate scope spanning factory/aca/aca_runner) and AGENTS.md documentation update (the two runtime knobs and active_tools mechanism are already documented in the config docs and code comments; deferring to keep this diff scoped to the review findings). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Jason Robert (jrob5756)
marked this pull request as ready for review
August 24, 2026 17:32
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Summary
The Copilot SDK does not guarantee any events during a tool call —
tool.execution_progressandtool.execution_partial_resultexist in theSDK schema but are opt-in per tool, so for most tool calls nothing arrives
between
tool.execution_startandtool.execution_complete. A stale idleclock during a long-running tool call was previously indistinguishable
from a genuinely stuck session — triggering a spurious "please continue"
recovery prompt mid tool-call. That prompt's conversational reply then
overwrote the agent's eventual structured output (
response_contentislast-message-wins), turning a healthy run into a non-retryable failure.
In-flight tool calls (tracked by
tool_call_id) now suppress idlerecovery entirely while any remain outstanding;
max_session_secondsisthe sole backstop for a genuinely wedged tool (
max_agent_iterationscannot help here — its counter only advances on a new
tool.execution_start, so it's frozen for the entire duration of awedge). Recovery-prompt and stuck-session messages also no longer
misattribute the failure to a tool that has already completed —
last_activity_ref's tool name is now cleared (or rolled to anotherstill-in-flight tool) on
tool.execution_completeinstead of only everbeing set. The first occurrence of extended suppression during a session
is logged at
warninglevel; further occurrences are debug-only.Also adds configurable
runtime.idle_timeout_secondsandruntime.max_idle_recovery_attempts(Copilot-only) so workflows withlegitimately long tool calls can tune the watchdog.
Closes#488
Testing
tests/test_providers/test_idle_recovery.pycoveringin-flight tool suppression, configurable timeouts, an end-to-end
regression test for the response-clobbering symptom, and the
warn-once suppression latch.
test_schema.py,test_factory.py,test_registry.pyforthe new runtime config fields.