The Agent Skills Directory

[EXTERNAL_DOWNLOADS]: The skill documentation and examples reference the use of the hookdeck-cli via npx for local development. This tool is a resource provided by the skill's author (hookdeck) to facilitate webhook testing. It also uses standard, well-known libraries such as @adyen/api-library and standard web frameworks.
[INDIRECT_PROMPT_INJECTION]: The skill provides logic to process external webhook payloads from Adyen. Although it implements robust authenticity checks, it handles untrusted data that could serve as a vector for indirect injection if not handled carefully in downstream systems.
Ingestion points: POST request handlers in examples/express/src/index.js, examples/fastapi/main.py, and examples/nextjs/app/webhooks/adyen/route.ts.
Boundary markers: HMAC-SHA256 signature verification is strictly enforced for every item in the notificationItems array, providing a strong trust boundary.
Capability inventory: The code examples demonstrate processing logic focused on logging transaction statuses and acknowledging receipt. No high-risk operations like system command execution or unauthorized file modifications are performed with the input data.
Sanitization: Authenticity is verified using the Adyen-provided HMAC secret. The implementations utilize timing-safe comparison functions to mitigate side-channel attacks.

adyen-webhooks