Skill: gandli/ctf-writeup (version 1.0.0)

--- name: ctf-writeup description: Generates a single standardized submission-style CTF writeup for competition handoff and organizer review. Use after solving a CTF challenge to document the solution steps, tools used, and lessons learned in a structured format. license: MIT compatibility: Requires filesystem-based agent (Claude Code or similar) with bash and Python 3. allowed-tools: Bash Read Write Edit Glob Grep Task WebFetch WebSearch metadata: user-invocable: "true" argument-hint: "[challenge-name]" --- # CTF Write-up Generator Generate a standardized submission-style CTF writeup for a solved challenge. Default behavior: - During an active competition, optimize for speed, clarity, and reproducibility - Keep writeups short enough that a teammate or organizer can validate the solve quickly - Always produce a `submission`-style writeup - Prefer one complete solve script from challenge data to final flag ## Workflow ### Step 1: Gather Information Collect the following from the current session, challenge files, and user input: 1. **Challenge metadata** — name, CTF event, category, difficulty, points, flag format 2. **Solution artifacts** — exploit scripts, payloads, screenshots, command output 3. **Timeline** — key steps taken, dead ends, pivots ```bash # Scan for exploit scripts and artifacts find . -name '*.py' -o -name '*.sh' -o -name 'exploit*' -o -name 'solve*' | head -20 # Check for flags in output files grep -rniE '(flag|ctf|eno|htb|pico)\{' . 2>/dev/null ``` ### Step 2: Generate Write-up Write the writeup file as `writeup.md` (or `writeup-<challenge-name>.md`) using the submission template below. --- ## Templates ### Submission Format ```markdown --- title: "<Challenge Name>" ctf: "<CTF Event Name>" date: YYYY-MM-DD category: web|pwn|crypto|reverse|forensics|osint|malware|misc difficulty: easy|medium|hard points: <number> flag_format: "flag{...}" author: "<your name or team>" --- # <Challenge Name> ## Summary <1-2 sentences: what the challenge was and the core technique. Keep it direct.> ## Solution ### Step 1: <Action> <Explain the key observation in 3-8 short lines. Keep it direct.> \`\`\`python <one complete solving script from provided challenge data to printing the final flag> \`\`\` ### Step 2: <Action> (optional) <Only add this when a second short step genuinely helps readability, such as separating the core observation from final verification.> ### Step 3: <Action> (optional) <Use only if the challenge really needs it. Keep the total number of steps small.> ## Flag \`\`\` flag{example_flag_here} \`\`\` ``` Guidance: - Prefer 1-3 short steps total - Keep code to the smallest complete solving script - Do not split "recover secret", "derive key", and "decrypt flag" into separate partial snippets - The script should start from the challenge data and end by printing the flag - Avoid long background sections - Avoid dead ends unless they explain a key pivot - Avoid multiple alternative solves; pick one clean path - Redact the flag only if the user explicitly asks for redaction --- ## Best Practices Checklist Before finalizing the writeup, verify: - [ ] **Metadata complete** — title, CTF, date, category, difficulty, points, author all filled - [ ] **Flag handling matches request** — keep the real flag unless the user asked for redaction - [ ] **Reproducible steps** — a reader can follow your writeup and reproduce the solution - [ ] **Code is runnable** — exploit scripts include all imports, correct variable names, and comments - [ ] **No sensitive data** — no real credentials, API keys, or private infrastructure details - [ ] **Length stays concise** — the writeup is short enough for fast review - [ ] **Tools and versions noted** — mention specific tool versions if behavior depends on them - [ ] **Proper attribution** — credit teammates, referenced writeups, or tools that were essential - [ ] **Grammar and formatting** — consistent heading levels, code blocks have language tags ## Quality Guidelines **DO:** - Explain just enough for fast verification - Include one complete solving path, not multiple alternative routes - Include one complete script that goes all the way to the final flag - Show actual output (truncated if very long) to prove the approach worked - Tag code blocks with language (`python`, `bash`, `sql`, etc.) - Keep the main path front-loaded so a reader can validate it quickly **DON'T:** - Copy-paste raw terminal dumps without explanation - Paste several partial snippets that force the reader to reconstruct the final solve - Leave placeholder text in the final writeup - Include irrelevant tangents that don't contribute to the solution - Assume the reader knows the specific challenge setup ## Challenge $ARGUMENTS


Security scan verdicts — ClawScan: clean | static analysis: clean | VirusTotal: clean | SkillSpector: clean (LOW)