Task output file grows unbounded — single file hit 107GB in 3 minutes

Bug Description

A single task output file in /private/tmp/claude-502/ grew to 107GB in ~3 minutes, consuming nearly all available disk space on a 500GB Mac (went from 65% to 96% usage overnight).

Details

• File: /private/tmp/claude-502/-Users-sarthakagrawal-Desktop-resume-tailor/tasks/bde8nuc08.output
• Size: 107GB (110,405 MB)
• Duration: ~3 minutes (10:55–10:58 UTC on 2026-03-05)
• Write rate: ~600 MB/second of JSONL logs
• Claude Code version: 2.1.69

Root Cause

Multiple subagents (ae85830b839d, ac1de4986f09, a139e167925a) were running concurrently in a resume-tailor project. All subagent progress events and messages were appended to a single shared .output file at an extreme rate. The file contains JSONL records of type progress, assistant, and user messages — mostly progress ticks from Bash commands (e.g., curl operations scraping web pages).

Sampling the file at 10GB intervals shows timestamps spanning only ~3 minutes, confirming this was a rapid, runaway write — not a slow accumulation.

Expected Behavior

Task output files should have a size cap or rotation policy. Writing 107GB of logs to /private/tmp in 3 minutes should not be possible.

Impact

• Filled disk from 65% to 96% usage
• User had no visibility into what consumed the space (macOS reports it as "System Data")
• The file was not automatically cleaned up

Environment

• macOS (Darwin 25.3.0, Apple Silicon)
• Claude Code 2.1.69
• 500GB disk

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