Dev.to tutorial Tutorials Oct 4 1 views

One Email Hijacked an AI Agent. Build a Tiny Prompt Injection Gate in TypeScript.

by Bobby Hall Jr

Content filters read text. Attackers encode text. Build a tiny Rule of Two gate in TypeScript that decides before the tool runs: mocked inbox, obedient mock model, three guards. No API key.

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Devto Id: 4796348
Reading Time Minutes: 10

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One Email Hijacked an AI Agent. Build a Tiny Prompt Injection Gate in TypeScript.

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