Document feedback-aware validation retries

docs/integrations/pkg-promptkit.md

@@ -15,7 +15,8 @@ Notarius relies on the root `promptkit` package to:
 - construct an `Engine` with filesystem-backed prompt, schema, and optional
   operator and application-fallback profile sources;
 - prepare one frozen execution from a `RunRequest` with named inline artifacts,
-  variables, a direct session ID, prompt identity, and profile selection, then
+  variables, a direct session ID, prompt identity, profile selection, and
+  optional appended rendered messages, then
   record credential-redacted details and run that exact execution;
 - return rendered debug material, validated structured output, selected
   profile, backend, effective model metadata, and token usage;
@@ -94,6 +95,23 @@ PromptKit v0.9.0 accepts only the `developer`, `system`, `user`, and
 `assistant` text-chat roles after normalizing case and surrounding whitespace.
 Maintained Notarius prompt definitions use only `system` and `user`.
 
+For application-owned semantic correction, Notarius uses PromptKit v0.9.0's
+`RunRequest.AppendedMessages` after the ordinary rendered prompt. It supplies
+exactly two messages in order: the latest validated producer response with
+role `assistant`, then deterministic validation guidance with role `user`.
+It never exposes a general caller-selected role API, accumulates earlier
+correction turns, or changes the ordinary prompt prefix. Ordinary requests
+leave appended messages unset.
+
+PromptKit preserves supplied content but does not own Notarius's correction
+bounds. Notarius rejects invalid UTF-8, blank, or oversized assistant material
+(at most 1 MiB), guidance (at most 64 KiB), and combined content (at most
+1,114,112 bytes) before preparing the request. The transport-neutral
+application contract owns defensive copying and these limits. Default request
+and terminal summaries retain only safe counts, digests, identities, and usage;
+complete appended messages remain limited to the explicitly requested detailed
+debug trace.
+
 PromptKit now obtains its maintained OpenRouter and Rakestrawhome backend and
 profile catalogs from independently versioned transitive modules. Notarius
 does not import or register either catalog; PromptKit retains catalog source,