Skill v1.0.0
currentAutomated scan100/100version: "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:
- Challenge metadata — name, CTF event, category, difficulty, points, flag format
- Solution artifacts — exploit scripts, payloads, screenshots, command output
- Timeline — key steps taken, dead ends, pivots
# Scan for exploit scripts and artifactsfind . -name '*.py' -o -name '*.sh' -o -name 'exploit*' -o -name 'solve*' | head -20# Check for flags in output filesgrep -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
---title: "<Challenge Name>"ctf: "<CTF Event Name>"date: YYYY-MM-DDcategory: web|pwn|crypto|reverse|forensics|osint|malware|miscdifficulty: easy|medium|hardpoints: <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
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