You Approved the Idea, Not the Payload — Seal the Bytes Before Your Agent Sends Them

Description and use

An automation recipe that ensures the outbound payload matches the approved bytes exactly by hashing a canonicalized representation.

Problem

Developers approve a prompt but the outbound request payload can be larger and contain additional data that was not reviewed, leading to unintended information disclosure.

Outcome

The script enforces that the exact bytes sent match the bytes approved, preventing accidental inclusion of unreviewed data.

Workflow

• 1. Capture the outbound payload JSON. 2. Canonicalize the payload by sorting keys and using compact separators. 3. Compute a SHA‑256 digest of the canonical payload. 4. Store the digest and section sizes as an approval file. 5. Before sending, recompute the digest and compare it to the stored approval. 6. If the digests match, send the payload; otherwise refuse to send and report the mismatch.
• 7. Optionally, use the "sizes" command to inspect section byte counts for debugging.

Evidence

I want an invariant a machine can enforce: the payload that leaves matches the payload a human approved, byte for byte, or the request does not leave.

Source

Here is the whole tool. It is about 70 lines and it has no dependencies beyond the standard library.

Source