Document consumer safety and offline execution

doc.go

@@ -18,6 +18,21 @@
 // isolated from engine state. Callers own those copies and may mutate them
 // after the call that supplied or returned them.
 //
+// # Security and sensitive data
+//
+// The default artifact reader treats [File] paths as caller-selected operating
+// system paths. It does not restrict them to an application root or impose an
+// inbound request-size policy. Promptkit is not an inbound request or
+// untrusted-input security boundary. Applications must validate and restrict
+// untrusted input before constructing a request, or install an [ArtifactReader]
+// that enforces their filesystem, authorization, and size policies.
+//
+// Rendered messages, input and output [Artifact] bodies, [RunResult.RawOutput],
+// and [ValidationResult.Errors] may contain sensitive data. Credential
+// exclusion and redaction do not sanitize those values. Applications and
+// injected collaborators are responsible for access control, retention,
+// logging, and secret handling appropriate to their data.
+//
 // # JSON
 //
 // Stable JSON representations are provided for [PreparedRun], [RunResult],