Plan mode auto-generated filename can produce inappropriate-sounding names

Preflight Checklist

• [x] I have searched existing issues for similar behavior reports
• [x] This report does NOT contain sensitive information (API keys, passwords, etc.)

Type of Behavior Issue

Other unexpected behavior

What You Asked Claude to Do

Plan mode auto-generated filename can produce inappropriate-sounding names

What Claude Actually Did

When entering plan mode, Claude Code auto-generates a random filename for the plan file using a pattern like adjective-verb-noun. In one instance, the generated filename
was:

twinkly-seeking-cocke.md

While "Cocke" is likely sourced from the computer scientist John Cocke, the resulting combination reads inappropriately and caused concern.

Expected Behavior

The random name generator should either:

• Filter out words/combinations that could be read as inappropriate
• Use a safer word list that avoids ambiguous surnames or words
• Allow users to configure or override the naming pattern

Files Affected

twinkly-seeking-cocke.md

Permission Mode

I don't know / Not sure

Can You Reproduce This?

No, only happened once

Steps to Reproduce

## Steps to Reproduce

1. Enter plan mode (via EnterPlanMode)
2. Observe the auto-generated plan filename in the system message

Claude Model

Opus

Relevant Conversation

That's the full plan — 7 steps across 9 files, all laid out with before/after for each change. Take a look and let me know if you'd like to adjust anything, or if we're
  good to start executing step by step.
  ⎿  Tool use rejected with user message: that file name is awful where did you get that from ? that seems really inappropiate ?

⏺ That name was auto-generated by the system — I agree, not great. Let me move it to something sensible.

⏺ Bash(cp /Users/djacura/.claude/plans/twinkly-seeking-cocke.md /Users/djacura/.claude/plans/fft-63286-sim-config-folder.md && rm /Users/djacura/.claude/plans/twinkly-…)
  ⎿  Done

Impact

High - Significant unwanted changes

Claude Code Version

2.1.66 — you can add that to the issue under Environment if you'd like.

Platform

Anthropic API

Additional Context

_No response_