Execute PromptKit requests from prepared snapshots

docs/integrations/pkg-promptkit.md

@@ -14,8 +14,9 @@ Notarius relies on the root `promptkit` package to:
 
 - construct an `Engine` with filesystem-backed prompt, schema, and optional
   profile sources;
-- prepare and run a `RunRequest` with named inline artifacts, variables,
-  a direct session ID, prompt identity, and profile selection;
+- prepare one frozen execution from a `RunRequest` with named inline artifacts,
+  variables, a direct session ID, prompt identity, and profile selection, 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;
 - register the optional conventional `local` backend through `BackendLocal`,
@@ -58,8 +59,9 @@ Notarius retains its application-wide scheduled client around the PromptKit
 adapter. PromptKit may apply a narrower limit for the selected backend;
 endpoint-only profiles have no such backend limit. The adapter translates
 PromptKit capacity rejection into the provider-neutral Notarius
-`ErrLLMCapacityExceeded` contract and leaves retries to the calling pipeline
-stage.
+`ErrLLMCapacityExceeded` contract. It may include the normalized selected
+backend ID in safe diagnostic context, without exposing PromptKit's capacity
+error type, and leaves retries to the calling pipeline stage.
 
 ## Notarius Ownership
 

docs/internal/llm.md

@@ -28,13 +28,14 @@ durable schemas. Those responsibilities remain with the module and its
 named material to a PromptKit inline artifact while preserving its origin URI,
 maps the trimmed request session to PromptKit's direct per-run session field,
 retains the same value as the `session_id` prompt variable for maintained
-prompt compatibility, forwards profile selection, then prepares and runs the
-prompt. The direct field is authoritative for provider session behavior. A
-session ID is a stable, non-secret correlation identifier and may be exposed
-to providers and provider observability. The adapter returns PromptKit’s
-validated raw bytes rather than re-encoding the decoded target. An empty
-optional material is represented as one space so its named input is retained
-by PromptKit.
+prompt compatibility, and forwards profile selection. It then creates one
+frozen prepared execution, captures its caller-owned credential-redacted
+details for debug material, and executes that exact snapshot. The direct field
+is authoritative for provider session behavior. A session ID is a stable,
+non-secret correlation identifier and may be exposed to providers and provider
+observability. The adapter returns PromptKit’s validated raw bytes rather than
+re-encoding the decoded target. An empty optional material is represented as
+one space so its named input is retained by PromptKit.
 
 Client construction may also receive a run-wide reasoning-effort override from
 the CLI factory boundary. The adapter copies the caller-owned pointer and
@@ -155,10 +156,12 @@ than output-validation failures.
 When PromptKit rejects backend admission before generation, the adapter maps
 `promptkit.ErrCapacityExceeded` to
 `contracts.ErrLLMCapacityExceeded`, retaining prompt context and a redacted
-upstream diagnostic without exposing the PromptKit sentinel as a framework
-contract. A canceled caller context takes precedence. The adapter does not
-retry capacity failures; the pipeline's existing binding attempt policy sees
-the operational error and decides whether to rerun the complete operation.
+upstream diagnostic without exposing the PromptKit sentinel or capacity-error
+type as a framework contract. When supplied, the normalized selected backend
+ID appears only in that safe application-owned diagnostic context. A canceled
+caller context takes precedence. The adapter does not retry capacity failures;
+the pipeline's existing binding attempt policy sees the operational error and
+decides whether to rerun the complete operation.
 
 Prompt-declared repair is executed within PromptKit’s structured-output flow.
 The current production D&D prompt manifests set repair attempts to zero. That