Expose prompt inspection through the engine

types.go

@@ -339,6 +339,40 @@ type ProfileInspection struct {
 	APIKeyRequired bool
 }
 
+// PromptInputDefinition describes one declared prompt input.
+// It has no stable JSON representation.
+type PromptInputDefinition struct {
+	// Name is the normalized prompt input name.
+	Name string
+	// Required reports whether preparation requires the input.
+	Required bool
+	// ContentType is the declared input media-type metadata.
+	ContentType string
+	// Description is the declared human-readable input description.
+	Description string
+}
+
+// PromptInspection is the caller-owned result of [Engine.InspectPrompt].
+// It has no stable JSON representation.
+//
+// Inputs contains copied declared input metadata in definition order.
+// OutputContract is the normalized contract declared by the prompt definition,
+// rather than a request-level effective override. PromptHash is opaque.
+type PromptInspection struct {
+	// PromptID is the normalized ID of the selected prompt definition.
+	PromptID string
+	// PromptVersion is the normalized version of the selected prompt definition.
+	PromptVersion string
+	// PromptHash is the opaque equality value for the selected definition.
+	PromptHash string
+	// DefaultProfileID is declared metadata and is not resolved by inspection.
+	DefaultProfileID string
+	// Inputs contains caller-owned declared input metadata in definition order.
+	Inputs []PromptInputDefinition
+	// OutputContract is the normalized contract declared by the definition.
+	OutputContract OutputContract
+}
+
 // ExecutionTargetOverride represents per-request runtime setting overrides and
 // has no stable JSON representation.
 //