Claude Code exits with code 1 before making API calls (worked 2 hours ago)

# Bug Report: Claude Code Action Crashing on All Requests

## Summary
Claude Code action is failing with exit code 1 on all requests as of ~2 hours ago (around 18:30 UTC, January 8, 2026), despite working perfectly just 2 hours prior. The action crashes before making any API calls (0 cost, <1 second duration).

## Environment
- **Action Version**: `anthropics/claude-code-action@v1`
- **Time of Failures**: Started around 20:30 UTC, January 8, 2026
- **Last Known Working**: Around 18:30 UTC, January 8, 2026 (~2 hours before failures)
- **Number of Affected Repositories**: 19 repositories (all experiencing same issue)
- **GitHub Actions Runner**: `ubuntu-latest`

## What Worked Previously (2 hours ago, ~18:30 UTC)
Simple query executed successfully across all 19 repositories:
```
@claude what files are in this repository?
```
- ✅ Completed successfully
- ✅ Returned file listings
- ✅ No errors

## What's Failing Now (Started ~20:30 UTC, January 8, 2026)
**ALL requests fail**, including trivial ones:

### Failed Request Examples:
1. **Comprehensive audit** (understandably complex):
```
@claude Please conduct a comprehensive optimization audit:
[...detailed requirements...]
```

2. **Simple focused request** (should be straightforward):
```
@claude Please analyze package.json and find:
1. Unused dependencies (packages imported but never used)
2. Duplicate or redundant packages
3. Heavy packages that could be replaced with lighter alternatives
```

3. **Minimal read-only request** (absolutely trivial):
```
@claude Please read package.json and list all dependencies in the "dependencies" and "devDependencies" sections. Just list them, no analysis yet.
```

**All three fail with identical error.**

## Error Details

### Error Message:
```
error: Claude Code process exited with code 1
at getProcessExitError (/home/runner/work/_actions/anthropics/claude-code-action/v1/base-action/node_modules/@anthropic-ai/claude-agent-sdk/sdk.mjs:7850:14)
at exitHandler (/home/runner/work/_actions/anthropics/claude-code-action/v1/base-action/node_modules/@anthropic-ai/claude-agent-sdk/sdk.mjs:7975:28)
```

### Key Indicators:
```json
{
"type": "result",
"subtype": "success",
"is_error": true,
"duration_ms": 364,
"num_turns": 1,
"total_cost_usd": 0,
"permission_denials": []
}
```

**Critical observations:**
- `duration_ms`: 364-946ms (crashes almost immediately)
- `total_cost_usd`: 0 (never reaches Claude API)
- `is_error`: true despite `subtype: "success"`
- No permission denials

### Subsequent Errors:
After main crash, GitHub API 404 errors occur (likely expected since no branch was created):
```
HttpError: Not Found - https://docs.github.com/rest/commits/commits#compare-two-commits
status: 404,
request: {
method: "GET",
url: "https://api.github.com/repos/JG003/anabasis/compare/main...claude%2Fissue-6-20260108-2050",
...
}
```

## Workflow Configuration

### `.github/workflows/claude.yml`:
```yaml
name: Claude PR Action
on:
issue_comment:
types: [created]
pull_request_review_comment:
types: [created]
issues:
types: [opened, assigned]
permissions:
contents: write
pull-requests: write
issues: write
id-token: write
jobs:
claude-pr:
if: |
(github.event_name == 'issue_comment' && contains(github.event.comment.body, '@claude')) ||
(github.event_name == 'pull_request_review_comment' && contains(github.event.comment.body, '@claude')) ||
(github.event_name == 'issues' && contains(github.event.issue.body, '@claude'))
runs-on: ubuntu-latest
steps:
- name: Checkout repository
uses: actions/checkout@v4

- name: Run Claude Code
uses: anthropics/claude-code-action@v1
with:
anthropic_api_key: ${{ secrets.ANTHROPIC_API_KEY }}
github_token: ${{ secrets.GITHUB_TOKEN }}
```

## What Has NOT Changed
- ✅ Workflow configuration (identical)
- ✅ API keys (verified working)
- ✅ Repository permissions (admin access confirmed)
- ✅ GitHub secrets (ANTHROPIC_API_KEY and GITHUB_TOKEN both set)
- ✅ Repository structure

## What May Have Changed
Since the user environment remained constant, the issue likely stems from:
- **Claude Code action update** (v1 may have auto-updated to broken version)
- **Anthropic backend issue**
- **GitHub Actions environment change**

## Reproduction Steps
1. Set up any repository with the workflow above
2. Create an issue with `@claude [any request]`
3. Observe immediate crash with exit code 1

## Expected Behavior
Claude Code should:
1. Initialize successfully
2. Read the repository context
3. Make API call to Claude
4. Update GitHub comment with response

## Actual Behavior
Claude Code:
1. Initializes
2. Crashes immediately (exit code 1)
3. Never reaches Claude API (0 cost)
4. Leaves generic "I'll analyze this and get back to you" comment

## Additional Context
- This affects **19 different repositories** with identical symptoms
- Repository type: React + TypeScript + Vite (Lovable-generated sites)
- Repository size: ~134 files (not unusually large)
- **Critical timing**: Repositories were just set up ~2 hours ago, worked perfectly for initial "what files are in this repository" queries, then immediately started failing on all subsequent requests
- The timing (working at 18:30 UTC, failing at 20:30 UTC - just 2 hours apart) strongly suggests an upstream change or incident

## Sample Job Run URLs
(From one affected repository - Anabasis)
- Failed run: https://github.com/JG003/anabasis/actions/runs/20831315372
- Issue where reported: https://github.com/JG003/anabasis/issues/6

## Requested Action
Please investigate what changed in the past 2 hours (~18:30-20:30 UTC, January 8, 2026) that would cause Claude Code to crash before making API calls. This appears to be a systemic issue affecting multiple repositories and all types of requests, suggesting a recent deployment or backend change.

---

**Reporter**: JG003
**Date**: January 8, 2026
**Severity**: Critical (complete service failure)