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Engineering Guides

4 essays, October 2026 to October 2026. 377 claims across 4 of them are checked against a primary source in the public ledger.

01 · Every essay in this strand

  1. What Is Prompt Injection? How to Stop a Tricked AI Agent Leaking Your Data

    One GitHub issue got an agent to post private-repo data in public. Why no filter fully stops it, which guards held in our runs, and how to test yours.

    108 sourced claims
  2. Claude Code Skills: How They Work, How to Write One, and How to Check Claude Uses It

    Claude picks a skill from its name and description. How to write the two lines it reads, and check it chose yours.

    83 sourced claims
  3. AI Agent Permissions: How to Stop Your Agent Doing Something You Can't Undo

    Our deny rule stopped one spelling of a branch delete and missed the next. The guards that hold for agent actions you can't undo, and how to test yours.

    101 sourced claims
  4. What Is Harness Engineering? How to Build AI Agents That Catch Their Own Mistakes

    Lessons from OpenAI, Anthropic, Google and independent engineers, worked through one failure, with a way to test every change.

    85 sourced claims

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