Reuse shared context without confusing tenants
one move: share immutable prefixes
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.
Prefix caching saves prefill work only when requests share an exact, safe prefix; tenant and policy boundaries are part of the cache key.
Deliverable: State the system invariant in one sentence.Group prompts by tenant and token prefix, compute shared-token savings, and never reuse a prefix across policy scopes.
Deliverable: Type the deterministic core.Identical prefixes share work, different scopes do not, and savings are computed from token counts rather than request counts.
Deliverable: Record a normal case and a boundary case.Change one token, tenant, or system policy and observe the cache miss.
Deliverable: Name the failure signal and its guard.A prefix-cache plan with hit rate, saved tokens, and isolation evidence.
Deliverable: Save the contract, evidence, and handoff note.Identical prefixes share work, different scopes do not, and savings are computed from token counts rather than request counts.
Change one token, tenant, or system policy and observe the cache miss.
A prefix-cache plan with hit rate, saved tokens, and isolation evidence.
Deriva-authored extension beyond the supplied PDF. The five moves are Deriva’s implementation contract for this project.