🤖 Fix test flake by simplifying prompt and clarifying unlimited steps #406
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Reasoning models (especially gpt-5-codex) can get stuck in infinite tool call loops when combined with web_search and high reasoning effort. This was causing the openai-web-search.test.ts integration test to timeout after 120+ seconds with 15+ tool calls and no completion. Root cause: The stream was using `stopWhen: stepCountIs(100000)` which effectively allowed unlimited tool calls. With reasoning models, the model can keep calling tools indefinitely without reaching a final answer. Fix: Replace unlimited steps with `maxSteps: 25` to prevent infinite loops while still allowing reasonable multi-turn tool use. This value is chosen based on observed failure (15 tool calls) with some buffer. The AI SDK will now stop the stream after 25 tool call rounds, ensuring the stream completes and emits stream-end even if the model gets stuck. Fixes: https://github.com/coder/cmux/actions/runs/18766377932
…oops" This reverts commit 5d49733.
The openai-web-search.test.ts was flaking because the prompt (gold price + Collatz sequence computation) was too complex and causing the reasoning model to enter excessive tool call loops that didn't complete within 120s. Changes: 1. **Clarified unlimited steps intent**: Added comment explaining that models MUST be able to run for hours or days with unlimited tool calls for autonomous workflows. The 100k step limit is intentionally high. 2. **Simplified test prompt**: Changed from complex math (Collatz on price²) to simple weather + picnic decision. This still tests reasoning + web_search combination but is much less likely to cause excessive loops. 3. **Reduced thinking level**: Changed from 'high' to 'medium' to avoid excessive deliberation while still ensuring reasoning is present. 4. **Adjusted timeouts**: Reduced from 150s/120s to 120s/90s since simpler task should complete faster. The test still validates the original bug fix (itemId errors with reasoning + web_search) but with a more stable prompt that's less likely to timeout. Fixes: https://github.com/coder/cmux/actions/runs/18766377932
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Problem
The
openai-web-search.test.tsintegration test was flaking in CI with timeouts after 120+ seconds:stream-endCI Run: https://github.com/coder/cmux/actions/runs/18766377932/job/53542148133
Root Cause
The test prompt was too complex for a reasoning model:
With
thinkingLevel: 'high'+web_search, this caused the model to enter excessive tool call loops:This is NOT a bug in the unlimited steps configuration - models MUST be able to run for hours or even days with unlimited tool calls for autonomous workflows.
Solution
Clarified unlimited steps intent: Added comment explaining that the 100k step limit is intentionally high to support long-running autonomous workflows
Simplified test prompt: Changed to simple weather query + picnic decision
Reduced thinking level: Changed from
hightomediumto avoid excessive deliberationAdjusted timeouts: Reduced to 120s/90s for simpler task
Testing
Type checking passes. The test still validates the same bug fix with a more stable prompt.
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