Essential Custom Instructions for Claude to Prevent Common Annoyances

A Reddit user on r/ClaudeAI shared three custom instructions they've refined to make working with Claude smoother, addressing specific annoyances they frequently encounter.
Three Essential Rules
The user identified three problematic patterns and created corresponding rules:
- No destructive commands without warning: Before suggesting any command that stops, removes, recreates, or changes ports of anything currently working (examples given:
docker stop,docker rm, service restarts), Claude must warn explicitly in bold that this will break things and ask for confirmation before proceeding. - No mid-answer plan changes: Claude should never start giving a plan and then change direction midway through the same answer. The model should decide the correct approach first, then provide one clear, linear plan to execute. If unsure, it should ask a clarifying question before starting.
- Code blocks are strictly for CODE: Never put conversational text, explanations, or follow-up instructions inside Markdown code blocks. Code blocks must contain exclusively functional, one-click copy-pasteable code. All explanations or separators should be placed outside the block, either above or below it.
The user describes these as "3 simple requests which I wished were already implemented by Anthropic in all Claude models" and invites others to share their must-have custom instructions in the comments.
📖 Read the full source: r/ClaudeAI
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