[BUG] Session freezes when reading persisted-output tool-results file after large Bash output #18095

Preflight Checklist

• I have searched existing issues and this hasn't been reported yet
• This is a single bug report (please file separate reports for different bugs)
• I am using the latest version of Claude Code

What's Wrong?

Claude Code session freezes indefinitely when attempting to Read a tool-results file that was created from a large Bash command output (<persisted-output>).

When Bash output exceeds ~30KB, it gets saved to a tool-results file. When Claude then tries to Read that file, the session becomes completely unresponsive - stuck in "Perusing..." state. Escape key does not work, and Ctrl+C requires multiple presses to interrupt. Only recovery is force exit and claude --continue.

What Should Happen?

Claude should successfully read the tool-results file and continue processing normally.

Error Messages/Logs

No error message displayed. Session simply hangs with no output.

The last visible output before freeze:
● Read(~/.claude/projects/.../tool-results/toolu_xxx.txt)

Then nothing - no response, no error, just frozen.

Steps to Reproduce

1. Run a Bash command that produces large output (>30KB):
   gh pr diff

2. Observe the output is saved to a persisted-output file:

3. Claude attempts to Read the persisted tool-results file to analyze the diff

4. Session freezes - no response, stuck state

Note: The freeze occurs specifically when Claude's Read tool attempts to access the tool-results file created from large Bash output. Tested with gh pr diff producing ~34KB output.

Claude Model

Opus

Is this a regression?

Yes, this worked in a previous version

Last Working Version

2.1.6

Claude Code Version

2.1.7

Platform

AWS Bedrock

Operating System

Ubuntu/Debian Linux

Terminal/Shell

VS Code integrated terminal

Additional Information

Potentially Related Issues

• [BUG] Claude Code Session Freeze on Large File Read Error (v2.1.1 - v2.1.3) #17394 - Session freeze on large file Read error (similar freeze behavior)
• Phantom Reads: Claude Does Not Follow Up on Persisted Output Read Results #17407 - Phantom Reads with persisted-output (same persisted-output mechanism)

v2.1.7 Changelog Reference

v2.1.7 changelog mentions: "Fix orphaned tool_result error when sibling tool fails during streaming" - this fix may have introduced the regression.

Workaround

Split large outputs before execution:
gh pr diff 2121 | head -200
# or
gh pr diff 2121 -- specific/file.rb

Environment

• Running in GitHub Codespaces (Linux container)
• Issue does not occur when Bash output is small enough to display inline