Codex’s Hidden Payload: 42 KB Request Reveals Tool Definitions and Context
A developer wired Codex to a local server and captured the exact HTTP request for a 16‑character prompt, finding it measured 42,980 bytes (≈9,400 tokens). Most of that payload is not the user prompt but Codex‑generated instructions, tool specs, permissions, and environment data, showing the model’s hidden context overhead.