diff --git a/src/agents/pi-embedded-runner/assemble-runtime-context.ts b/src/agents/pi-embedded-runner/assemble-runtime-context.ts
index 7f7a8973fca..2c3b3e11b27 100644
--- a/src/agents/pi-embedded-runner/assemble-runtime-context.ts
+++ b/src/agents/pi-embedded-runner/assemble-runtime-context.ts
@@ -12,6 +12,12 @@ export type EmbeddedAssembleRuntimeContext = {
   reservedContextTokensEstimate?: number;
 };
 
+type AssembleRuntimePromptReport = {
+  systemPrompt?: Pick<SessionSystemPromptReport["systemPrompt"], "chars"> | null;
+  skills?: Pick<SessionSystemPromptReport["skills"], "promptChars"> | null;
+  tools?: Pick<SessionSystemPromptReport["tools"], "listChars" | "schemaChars"> | null;
+};
+
 function normalizeChars(value: unknown): number {
   if (!Number.isFinite(value) || Number(value) <= 0) {
     return 0;
@@ -29,7 +35,7 @@ function estimateTokensFromChars(chars: number): number {
 export function buildEmbeddedAssembleRuntimeContext(params: {
   systemPromptText?: string | null;
   prompt?: string | null;
-  systemPromptReport?: Pick<SessionSystemPromptReport, "systemPrompt" | "skills" | "tools"> | null;
+  systemPromptReport?: AssembleRuntimePromptReport | null;
 }): EmbeddedAssembleRuntimeContext {
   const report = params.systemPromptReport ?? undefined;
   const systemPromptChars = normalizeChars(