Intermittent API 500 errors during tool calls (Write, large output)

Description

Getting intermittent API 500 errors (api_error: Internal server error) during Claude Code sessions. Two occurrences in a single session (~90 min), both during tool calls that produce or process large outputs.

Request IDs

1. req_011Ca21cgCgRpSZ8s59e7zKJ — occurred during/after a series of git commit calls with large pre-commit hook output (lint + build + EDD check for 9 NestJS projects, ~200 lines per commit × 5 atomic commits)
2. req_011Ca228BYbC2iWtvaLVfkMv — occurred during a Write tool call creating a 160-line markdown file (eval report)

Environment

• Platform: Windows 11 (win32)
• Shell: Git Bash
• Model: claude-opus-4-6 (1M context)
• Interface: VSCode extension
• Session context: Moderately large (~60+ tool calls, EDD development cycle with multiple file reads, writes, and bash commands)

Behavior

• Both errors are transient — the operations appear to complete after the error (file was written, commits went through)
• The errors disrupt the conversation flow (user sees the raw 500 JSON)
• Both occurred during periods of heavy tool use with large outputs

Reproduction

Not deterministic, but the pattern suggests correlation with:

• Large tool output (pre-commit hooks running lint+build across 9 projects)
• Accumulated context size in long sessions
• Rapid sequential tool calls

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