AI Sec Watch: A Security Intelligence Platform for AI Systems

Luu, T.J.

Skills in OpenAI API

infonewsLLM-Specific

industry

Source: Simon Willison's WeblogFebruary 11, 2026

Summary

OpenAI now allows developers to use Skills (reusable code packages) directly in the OpenAI API through a shell tool, with the ability to upload Skills as compressed files or send them inline as base64-encoded zip data (a way of encoding binary files as text) within JSON requests. The example shows how to create an API call that uses a custom skill to count words in a file, making it easier to extend AI capabilities with custom tools.

Classification

Attack SophisticationTrivial

AI Component TargetedAPI

Affected Vendors

OpenAI

Related Issues

high

Anthropic accuses Chinese AI labs of mining Claude as US debates AI chip exports

Same vendorTechCrunch

info

Anthropic and the Pentagon are back at the negotiating table, FT reports

Same vendorCNBC Technology

Original source: https://simonwillison.net/2026/Feb/11/skills-in-openai-api/#atom-everything

First tracked: February 12, 2026 at 02:28 PM

Classified by LLM (prompt v3) · confidence: 85%