Claude Code Best Practices

Language Rule

• Always respond in the same language the user is using. If the user asks in Chinese, respond in Chinese. If in English, respond in English.

Context Management Rules

Rule	Why
One window = one task	Mixing tasks pollutes context and degrades output quality
Use /clear over /compact	Clean start is more reliable than compressed context
/clear after complex tasks	Prevents old context from interfering with new work
Copy key info to new windows	Don't rely on context persistence — paste critical details

Task Execution Strategy

Task Type	Recommended Approach
Small bug fix (few lines)	Describe directly, let Claude modify in-place
Large feature / refactor	/plan → review approach → /clear → paste plan → execute step by step
Multi-file changes	Must use /plan workflow — never modify multiple files without a plan
Code analysis / learning	Ask Claude to analyze directly — no plan needed
Debugging	Provide error message + file path + relevant code — ask for root cause

Prompt Techniques

Do This

• Give specific paths: "Modify the _transfer function in src/MyToken.sol"
• Give examples: "Input: 100 tokens, Expected: 95 tokens after 5% fee"
• Set boundaries: "Only modify this function, don't touch other code"
• Reference tests: "The fix should make test_transfer_feeDeduction pass"

Avoid This

• Vague references: "Modify that transfer function" — which one? Where?
• Open-ended requests without constraints: "Make it better"
• Multiple unrelated tasks in one message

Git Operation Rules

• Always run git diff before committing to review changes
• Only commit — do not push unless explicitly requested
• Never push directly to main/master branch
• Stage specific files — never use git add . in Solidity projects (risk of committing .env)

Foundry-Specific Workflow

Action	Command
Before committing	forge fmt && forge test
After modifying contracts	forge build to check compilation
Before PR	forge test --gas-report to check gas impact
Debugging failed test	forge test --match-test <name> -vvvv for full trace

Quick Command Reference

Command	Purpose
/clear	Clear context, start fresh
/plan	Enter planning mode — analyze before modifying
/help	View all available commands
/compact	Compress context (prefer /clear instead)

Project-level Configuration

Create .claude/instructions.md in the project root with project-specific rules. Claude automatically reads it at the start of every conversation — no manual loading needed.