Show Me the Receipts

Josh Rosen (@JoshARosen on X) posted "Show Me the Receipts: The Case for Immutable Artifacts for Agent Work," and it is the engineering half of an argument I keep making from the legal side.

His case: agents should leave receipts as they work. Typed artifacts, immutable once written, required as a condition of doing the work, each one referencing the exact versions of the upstream work it relied on. The agent keeps its freedom in how it works; it loses the ability to redefine what "done" means.

The receipts get produced inside the work, so part of the process lives outside the agent. An agent reporting "investigation complete" is the agent grading its own work. The audit can't share a source with the work.

And the version pinning. An assessment that references the exact usage analysis in hand at the time can answer the question disputes turn on: what did the system know when it decided? I track legal AI systems closely. I have yet to see one ship that binding.

For legal and product teams, the reason to care is what happens later: a regulator, opposing counsel, or your own incident review shows up to check, and the record is the only account of the decision that will exist. Capability without a record is capability you cannot use.

Josh ends with the right instruction. When the agent says the work is finished, ask to see the receipts.