offensive-tools/api/arjun/SKILL.md
Discover hidden HTTP parameters in web endpoints. Use when performing API reconnaissance, fuzzing query/body/header parameters, or finding undocumented inputs in REST/GraphQL endpoints.
npx skillsauth add aeondave/malskill arjunInstall this skill globally with one command. Works with Claude Code, Cursor, and Windsurf.
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HTTP parameter discovery — finds hidden GET/POST/JSON/XML parameters in web endpoints.
pip install arjun
# Single URL — GET params
arjun -u https://target.com/api/endpoint
# POST body params
arjun -u https://target.com/api/endpoint -m POST
# JSON body
arjun -u https://target.com/api/endpoint -m JSON
# Multiple URLs from file
arjun -i urls.txt -o results.json
| Flag | Purpose |
|------|---------|
| -u URL | Target URL |
| -m GET/POST/JSON/XML | Request method (default: GET) |
| -i FILE | Input file with URLs |
| -o FILE | Output results to JSON |
| -t N | Threads (default: 5) |
| -d N | Request delay (ms) |
| --headers "K:V" | Custom headers |
| --stable | Avoid flakey endpoints (retry on error) |
| -q | Quiet mode |
| --include | Always include params in every request |
API recon on authenticated endpoint:
arjun -u https://api.target.com/v1/user -m GET --headers "Authorization: Bearer TOKEN"
Fuzz POST form:
arjun -u https://target.com/login -m POST
Batch scan from Burp export:
cat burp_urls.txt | arjun -i /dev/stdin -o found_params.json
| File | When to load |
|------|--------------|
| references/ | Extended wordlist and tamper tips |
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