Qwen Code loop detection falsely halts multi-agent coordination

netbrah · ghdev · 2026-08-19

Qwen Code Issue #9450 reports a critical bug where the loop detection mechanism incorrectly interrupts multi-agent collaboration by flagging valid tasklist calls as a duplicate loop.

Problem Details:

An agent teammate was stopped with a “duplicate tool-call loop detected” error while coordinating with peers.
Root Cause: The agent repeatedly queried tasklist to check peer status (e.g., completion, failure, or dependency updates). Although the arguments were identical, the results were stateful and changed over time, meaning it was not a deterministic loop.
Impact: The current logic evaluates repetition based solely on tool name and parameters, ignoring result state changes. This caused the agent to be forcibly terminated after 93 requests.

Expected Fix:

Modify the loop detection logic to account for stateful coordination tools like tasklist.
Termination should not occur based solely on repeated arguments; the actual execution result must be considered.

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Qwen Code loop detection falsely halts multi-agent coordination

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