Stop a prompt injection before it reaches a tool
one move: constrain the capability
Open the code pane immediately, then use the Spec tab, optional design question, tests, and artifact when you want them.
Finish each move before carrying the artifact forward.
A model-facing tool gateway must validate content, requested capability, and size before dispatch; policy is part of the API.
Deliverable: State the invariant in one sentence.Reject common instruction-overrides, unknown tools, and oversized requests; return a structured allow/reason decision.
Deliverable: Type the smallest deterministic implementation.Safe requests pass, policy violations abstain with one stable reason, and the gateway never mutates the input.
Deliverable: Record a normal case and a boundary case.Try casing changes, encoded instruction text, an unknown tool, and a request over the limit.
Deliverable: Name the failure signal and the guard you would add.A policy decision log, allowlist, and red-team fixture set.
Deliverable: Save the contract, evidence, and handoff note.Safe requests pass, policy violations abstain with one stable reason, and the gateway never mutates the input.
Try casing changes, encoded instruction text, an unknown tool, and a request over the limit.
A policy decision log, allowlist, and red-team fixture set.
Deriva-authored extension beyond the supplied PDF. The five moves are Deriva’s implementation contract for this project.