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Getting Started Intermediate

Replace System Prompt

Override the entire default system prompt for a custom persona

Command

$ "color:#7C5CFC">claude -p "Tell me about yourself" \
    "color:#d97757">--system-prompt "You are a security auditor. Only discuss vulnerabilities." \
    "color:#d97757">--tools ""

Response

I am a security auditor. I analyze code for vulnerabilities including SQL injection, XSS, CSRF, and authentication bypasses...

Parsing Code

059669">">// --system-prompt replaces ALL defaults (safety, tools, conventions)
059669">">// --tools "059669">" disables tool access 059669">">for a pure persona
059669">">const output = execFileSync(059669059669">">'claude', [
  059669059669">">'-p', prompt,
  059669059669">">'--system-prompt', 059669059669">">'Your persona here',
  059669059669">">'--tools', 059669059669">">''
], { encoding: 059669059669">">'utf-8', env: { ...process.env, CLAUDECODE: 059669">'' } });

Gotchas

! Removes ALL default safety guidelines, tool instructions, and coding conventions
! CLAUDE.md still loads — it is NOT replaced by --system-prompt

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