Claude Code CLI crashes on startup in CI (exit code 1, ajv schema validation)

[zsprackett]

Description

The Claude Code CLI crashes during startup in GitHub Actions with exit code 1, before making any API calls ($0 cost, 183ms duration). This appears to be a schema validation error in ajv.

Environment

• Action: anthropics/claude-code-action@v1
• Agent SDK: @anthropic-ai/claude-agent-sdk@0.2.42
• Claude Code: v2.1.31 (bundled), also reproduced with latest via native installer
• Runner: ubuntu-latest
• Auth: OAuth token (claude_code_oauth_token)

Timeline

• Working: Feb 14, 2026 -- PR review completed successfully on push2 branch (20 turns, $0.65 cost)
• Broken: Feb 15, 2026 -- same workflow, same config, crashes on startup

Both runs used identical SDK options, identical Claude Code version (2.1.31), identical workflow file.

Reproduction

Minimal workflow that reproduces the issue:

name: PR Review
on:
  pull_request:
    types: [opened, synchronize]

jobs:
  claude-review:
    runs-on: ubuntu-latest
    permissions:
      contents: read
      pull-requests: read
      issues: read
      id-token: write
    steps:
      - uses: actions/checkout@v6
        with:
          fetch-depth: 1
      - uses: anthropics/claude-code-action@v1
        with:
          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
          prompt: "Review this PR"
          claude_args: '--allowed-tools "Bash(gh pr diff:*),Bash(gh pr view:*)"'

Error output

The SDK result shows immediate failure:

{
  "type": "result",
  "subtype": "success",
  "is_error": true,
  "duration_ms": 183,
  "num_turns": 1,
  "total_cost_usd": 0,
  "permission_denials": []
}

Followed by a minified JS stack trace from ajv schema validation (dependencies keyword handler):

SDK execution error: 14 |     depsCount: ${X},
15 |     deps: ${Y}}`};var Tj={keyword:"dependencies",type:"object",schemaType:"object",...
...
error: Claude Code process exited with code 1
      at Y (.../node_modules/@anthropic-ai/claude-agent-sdk/sdk.mjs:19:7919)
      at emit (node:events:98:22)
      at #handleOnExit (node:child_process:520:14)

What we tried

1. Re-running the job multiple times -- same failure
2. Installing latest Claude Code via native installer (curl -fsSL https://claude.ai/install.sh | bash) with path_to_claude_code_executable -- same crash
3. Installing via npm (npm install -g @anthropic-ai/claude-code@latest) -- SDK rejects non-native binary

Successful run for comparison

• Run ID: 22025297491 (Feb 14, push2 branch) -- succeeded
• Run ID: 22029616604 (Feb 15, email branch) -- failed
• Both used SDK 0.2.42, Claude Code 2.1.31, identical workflow, identical SDK options

Failing runs

• https://github.com/Brief-Solutions/brief/actions/runs/22029616604/job/63652731603
• https://github.com/Brief-Solutions/brief/actions/runs/22029979002/job/63653391172