Supabase Extract Jwt

Name: Supabase Extract Jwt
Author: yoanbernabeu

Checked

yoanbernabeu·vlatest·security

Helps with Supabase, data extraction, JWT as part of working with databases and data persistence workflows.

Repository

Install on your platform

Showing Claude Code. One command installs this skill into any of the agents below.

Run this in your project

terminal

$ npx skills add yoanbernabeu/supabase-pentest-skills --skill supabase-extract-jwt -a claude-code

Uses the open-source skills CLI and needs Node.js. Add -g to install it for your user instead of this project.

What we know about this skill

Publisher

yoanbernabeu

Taken from the source listing. We haven't verified who controls this account.

Install target

Live repository

Not pinned. Installing fetches whatever the repository holds at the time you run the command.

No human has reviewed this code. The checks below are a static scan of the files at one commit — nobody has run this skill or judged whether it works. A skill runs with whatever access you give your agent, so read the source before you install it.

Automated safety checks

scanned 27 Sept 2026

This skill passed all 6 checks. We read its files at one commit and looked for the things that make a skill dangerous to run — not for whether it works.

Declares what it does: passed
SKILL.md parses and declares a name and a description.
SKILL.md exists, its frontmatter parses, and it declares a name and a description.
No undeclared network calls: passed
Makes no network calls.
Every host the skill dials — from its scripts, its config endpoints or the commands it tells the agent to run — is either well-known package and API infrastructure or declared in its own frontmatter. Links in documentation are not counted.
No obfuscated payloads: passed
No encoded or obfuscated payloads.
No base64, hex or compressed blob is decoded and then executed, and no encoded shell commands.
No credential access: passed
Reads no keys, tokens, keychains or credential files.
Neither the code nor the SKILL.md instructions read SSH keys, cloud credentials, keychains, token stores, browser cookie databases or dotfiles that hold secrets.
No pipe-to-shell installers: passed
No pipe-to-shell or download-and-run installers.
No `curl … | sh` pattern, in the code or in the instructions, that runs code fetched at run time.
Pinned to a commit: passed
Scanned yoanbernabeu/supabase-pentest-skills at 0f9612276b.
The exact upstream commit SHA that was scanned is recorded, so the result refers to specific bytes.

Commit: 0f9612276b
Manifest: skills/extraction/supabase-extract-jwt/SKILL.md
Scanned: 1 file, 331 lines

This is a static scan, not a review. It reads the skill's files; it does not run them, and it cannot tell you whether the skill is any good or whether the code does what its description says. A skill runs with whatever access you give your agent.

What each check looks for →

About this skill

The supabase-extract-jwt skill parses Supabase JWT tokens to reveal embedded claims, enabling agents to inspect user identity data without executing database queries. It is designed for security auditing and debugging scenarios where understanding token payload structure is critical.

When to use it

Analyzing authentication tokens during penetration testing to verify scope and permissions.
Debugging session issues by decoding claims to identify missing or incorrect user attributes.
Validating that Supabase policies correctly restrict access based on specific JWT fields.
Inspecting token expiration and issuer details in a secure, read-only manner.

Key capabilities

Decodes standard Supabase JWT tokens automatically.
Extracts and displays all claims within the token payload.
Operates without requiring database write permissions or active connections.

Example prompts

"Extract the user ID and role from this Supabase JWT token: [paste_token_here]"
"Decode this authentication token and list all embedded claims for security review."
"What does this JWT token claim about the current session's expiration time?"

Tips & gotchas

Ensure you provide a valid, unexpired Supabase JWT token to avoid parsing errors. This skill is intended for inspection only; do not use extracted data to forge new tokens or bypass authentication controls.