What does the Sibylla skill do?

Secure your APIs where they actually break: authorization per object, a real endpoint inventory, and gateway and CI controls that hold. Load it once into Claude Projects and you get a configured API Security Engineer without re-explaining context at the start of every session. This skill is for authorized, defensive security work only. Validate findings in your own environment, follow your rules of engagement and written authorization, and confirm current framework, vendor, and regulatory specifics before you act on them.

How do I install this skill file?

Download the .skill package (it contains SKILL.md), paste the contents into Claude Projects Instructions or your AI's system prompt, add your own context and start your first session. Works with Claude, ChatGPT, or any AI chat that accepts system prompts.

Which AI tools does this skill work with?

Works with Claude (recommended), ChatGPT, Gemini, Perplexity and Copilot, and any AI chat that accepts system prompts. Claude Projects gives the best results.

What is included in this download?

One .skill package delivered instantly after purchase: the full SKILL.md role configuration plus a worked-example file with a real scenario so you see the quality before you rely on it. No subscription, yours permanently.

How is this different from using Claude without the Sibylla skill?

Without a skill file your AI starts every session as a general assistant. With Sibylla loaded it applies API Security Engineer methodology from the first message, with consistent quality every time. This skill is for authorized, defensive security work only. Validate findings in your own environment, follow your rules of engagement and written authorization, and confirm current framework, vendor, and regulatory specifics before you act on them.

API Security Engineer AI Skill for Claude

Name: Sibylla — API Security Engineer AI Skill
Brand: KissMySkills
Price: 14.99 USD
Availability: InStock

Sibylla — API Security Engineer AI Skill

$14.99

Sibylla — API Security Engineer AI Skill

$14.99 this skill vs $140+/hr, hiring an API security engineer

⚡ Instant download ◆ Claude & ChatGPT ∞ Keep forever

Instant download · 30-day money-back guarantee. Pay once, keep forever — no subscription. Refund policy

Secure your APIs where they actually break: authorization per object, a real endpoint inventory, and gateway and CI controls that hold.

BOLA, IDOR and function-level authorization testing
API discovery: shadow, zombie and undocumented endpoints
OAuth 2.0, OIDC, JWT validation and token lifetime design
Gateway, rate limit and abuse policy plus CI security testing

Product and platform teams shipping APIs fast who need authorization and inventory under control before someone enumerates their object IDs.An API security engineer bills $140+/hr, this is one file, yours forever.

// what's inside

Drop Sibylla into Claude and get an API security engineer who goes straight for broken object level authorization, because that is what is actually getting exploited.

Sibylla secures APIs as their own attack surface: the OWASP API Security Top 10 with BOLA and broken function-level authorization treated as the dominant real-world findings, API discovery and inventory including shadow, zombie and undocumented endpoints, schema and contract validation across OpenAPI, GraphQL and gRPC, authentication and authorization done properly with OAuth 2.0 grant selection, OIDC, JWT validation failures, scopes versus entitlements, token lifetime and revocation and mTLS for service-to-service, rate limiting and abuse prevention, gateway and WAAP policy on Kong, Apigee, AWS API Gateway and Cloudflare, mass assignment and excessive data exposure, webhook and callback security, machine-to-machine credentials, business logic abuse no scanner will find, API testing in CI and in production, and the third-party API you consume being your problem too.

What you get

→BOLA, IDOR and function-level authorization testing
→API discovery: shadow, zombie and undocumented endpoints
→OAuth 2.0, OIDC, JWT validation and token lifetime design
→Gateway, rate limit and abuse policy plus CI security testing

📄 sibylla-api-security-engineer.skill Under 2 min install Works with Claude, ChatGPT & any AI chat

How to install

Download the .skill package, open Claude, paste SKILL.md into your Project Instructions or system prompt, describe your requirement, and Sibylla builds the answer. Includes a full worked example so you see exactly what you get.

sibylla-api-security-engineer.skill

# Sibylla - API Security Engineer

You are Sibylla, a senior API security engineer. You start from authorization per object and a real endpoint inventory, because that is where APIs actually fail.

## How you work
1. Build the endpoint inventory, including what nobody documented
2. Test authorization per object and per function, not just authentication
3. Fix token design: grant type, lifetime, scope, revocation, validation
4. Apply gateway, rate limit and abuse policy to the real traffic shape
5. Encode the tests in CI so the next endpoint inherits them

Test only systems you are authorized to test. Confirm current specifications and vendor behaviour before relying on them.

Excerpt from the actual file you'll download.

// try it

prompt

$We have 300 endpoints, no inventory, and a scanner that finds nothing. Where are we actually exposed?

Sibylla returns an endpoint inventory approach with the shadow and zombie findings, an authorization test plan targeting BOLA and function-level flaws by object type, the token and OAuth design corrections, gateway and rate-limit policy, the CI test additions with real assertions, and the business-logic abuse cases a scanner cannot reach, with pentest execution routed to Malik.

// how to install Under 2 minutes

Four steps. Any AI chat.

01
Download the file
After checkout, the download link lands in your inbox. Save the file anywhere on your device.
02
Open your AI chat
Claude, ChatGPT, Gemini, Grok, or Copilot — whichever one you already use.
03
Paste the file contents
Drop it into the system prompt, Project instructions, or custom instructions field.
04
Start working
Your AI is now configured as a specialist. Ask it anything inside its domain.