Investigation: Auto-Triage Issues workflow failure - transient API error

[Copilot]

Workflow run #21186843566 failed with Error: missing finish_reason for choice 0 from Claude Sonnet 4.5.

Investigation Findings

Root Cause: Transient API error in Claude completion response
Status: Self-recovered - subsequent run #34 succeeded without changes
Action: None required

Evidence

Run history shows isolated incident:

#34 (2026-01-21 00:40) ✅ Success
#33 (2026-01-20 20:53) ❌ Failure ← investigated
#32 (2026-01-20 18:15) ✅ Success
#31-27: All successful

Agent completed work successfully before API error:

• Analyzed issue Campaign: Security Alert Burndown #10857
• Retrieved labels via GitHub MCP
• Generated classification report
• Failed during final API response processing

Technical Details

• Error: Claude API missing finish_reason field in response
• Token usage: 54.8k input, 844 output, 22.8k cache read
• Duration: 22s (16s API time)
• Workflow config: Correct, no changes needed

Recommendation

Close issue - transient error with confirmed self-recovery. Optional enhancement: add retry logic for API failures in Copilot CLI layer.

Original prompt

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This section details on the original issue you should resolve

<issue_title>[agentics] Auto-Triage Issues failed</issue_title>
<issue_description>### Workflow Failure

Workflow:Auto-Triage Issues
Branch: main
Run URL:https://github.com/githubnext/gh-aw/actions/runs/21186843566

Action Required

Debug this workflow failure using the agentic-workflows agent:

/agent agentic-workflows

When prompted, instruct the agent to debug this workflow failure.

Generated from Auto-Triage Issues

• expires on Jan 27, 2026, 8:55 PM UTC

Comments on the Issue (you are @copilot in this section)

• Fixes[agentics] Auto-Triage Issues failed #10899

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