[BUG] Model wastes excessive tokens in internal reasoning for simple file creation tasks

Preflight Checklist

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

What's Wrong?

## Description

When asked to create a simple PlantUML diagram file, the
model spent
approximately 90,000 tokens in internal reasoning
(thinking/scratchpad)
before producing any output.

Actual Behavior

~90,000 tokens consumed. Output quality was poor despite
the cost.

## Impact

• Wastes user's token quota
• No way to interrupt thinking before it completes
• User cannot get a refund for wasted tokens

What Should Happen?

## Expected Behavior

Model should pick a reasonable approach and write the file
directly.
2-3 source file reads + file creation = under 5k tokens
total.

Error Messages/Logs

Steps to Reproduce

Steps to Reproduce

1. Ask Claude Code to create a .puml diagram file

visualizing
layout templates from existing source files

1. The model reads 2 source files (justified)
2. Then enters a loop of internal deliberation (~15+

iterations)
comparing approaches (ditaa vs salt vs rectangle)
without
converging on a decision

1. Finally produces a low-quality result after consuming

massive
token budget

Claude Model

None

Is this a regression?

Yes, this worked in a previous version

Last Working Version

claude-sonnet-4-6

Claude Code Version

claude-sonnet-4-6

Platform

Anthropic API

Operating System

macOS

Terminal/Shell

Terminal.app (macOS)

Additional Information

_No response_