fix(context): address PR feedback on state persistence and snapshot rehydration

packages/core/src/context/contextManager.ts

@@ -43,9 +43,12 @@ export class ContextManager {
       history: Content[];
       didApplyManagement: boolean;
       baseUnits: number;
+      processedNodes: readonly ConcreteNode[];
     };
   };
 
+  private lastAppliedNodes?: readonly ConcreteNode[];
+
   private hasPerformedHotStart = false;
 
   constructor(
@@ -287,6 +290,7 @@ export class ContextManager {
     history: Content[];
     didApplyManagement: boolean;
     baseUnits: number;
+    processedNodes: readonly ConcreteNode[];
   }> {
     this.tracer.logEvent('ContextManager', 'Starting rendering of LLM context');
 
@@ -348,11 +352,7 @@ export class ContextManager {
     const protectionReasons = this.getProtectedNodeIds(nodes, activeTaskIds);
 
     // Apply final GC Backstop pressure barrier synchronously before mapping
-    const {
-      history: renderedHistory,
-      didApplyManagement,
-      baseUnits,
-    } = await render(
+    const renderResult = await render(
       nodes,
       this.orchestrator,
       this.sidecar,
@@ -364,6 +364,15 @@ export class ContextManager {
       previewNodeIds,
     );
 
+    const {
+      history: renderedHistory,
+      didApplyManagement,
+      baseUnits,
+      processedNodes,
+    } = renderResult;
+
+    this.lastAppliedNodes = processedNodes;
+
     // Structural validation in debug mode
     checkContextInvariants(this.buffer.nodes, 'RenderHistory');
 
@@ -379,6 +388,7 @@ export class ContextManager {
       }),
       didApplyManagement,
       baseUnits,
+      processedNodes,
     };
 
     // Update cache
@@ -434,7 +444,9 @@ export class ContextManager {
   }
 
   exportState(): ContextEngineState {
-    return SnapshotStateHelper.exportState(this.buffer.nodes);
+    return SnapshotStateHelper.exportState(
+      this.lastAppliedNodes || this.buffer.nodes,
+    );
   }
 
   restoreState(state: ContextEngineState): void {

packages/core/src/context/graph/render.ts

@@ -31,6 +31,7 @@ export async function render(
   history: Content[];
   didApplyManagement: boolean;
   baseUnits: number;
+  processedNodes: readonly ConcreteNode[];
 }> {
   let headerTokens = 0;
   let headerBaseUnits = 0;
@@ -52,7 +53,12 @@ export async function render(
     const baseUnits =
       advancedTokenCalculator.getRawBaseUnits(nodes) + headerBaseUnits;
 
-    return { history: contents, didApplyManagement: false, baseUnits };
+    return {
+      history: contents,
+      didApplyManagement: false,
+      baseUnits,
+      processedNodes: nodes,
+    };
   }
 
   const maxTokens = sidecar.config.budget.maxTokens;
@@ -97,6 +103,7 @@ export async function render(
       history: contents,
       didApplyManagement: false,
       baseUnits: graphBaseUnits + headerBaseUnits,
+      processedNodes: nodes,
     };
   }
   const targetDelta = currentTokens - sidecar.config.budget.retainedTokens;
@@ -151,5 +158,6 @@ export async function render(
     didApplyManagement: true,
     baseUnits:
       advancedTokenCalculator.getRawBaseUnits(visibleNodes) + headerBaseUnits,
+    processedNodes,
   };
 }

packages/core/src/context/graph/toGraph.ts

@@ -64,11 +64,12 @@ function isFunctionResponsePart(
 
 function isExecutableCodePart(
   part: Part,
-): part is Part & { executableCode: { code: string } } {
+): part is Part & { executableCode: { code: string; language: string } } {
   return (
     typeof part.executableCode === 'object' &&
     part.executableCode !== null &&
-    typeof part.executableCode.code === 'string'
+    typeof part.executableCode.code === 'string' &&
+    typeof part.executableCode.language === 'string'
   );
 }
 
@@ -78,7 +79,8 @@ function isCodeExecutionResultPart(
   return (
     typeof part.codeExecutionResult === 'object' &&
     part.codeExecutionResult !== null &&
-    typeof part.codeExecutionResult.output === 'string'
+    typeof part.codeExecutionResult.output === 'string' &&
+    typeof part.codeExecutionResult.outcome === 'string'
   );
 }
 
@@ -138,12 +140,16 @@ export function getStableId(
     id = `resp_h_${contentHash}_${turnSalt}_${partIdx}`;
   } else if (isExecutableCodePart(part)) {
     contentHash = createHash('sha256')
-      .update(`exec:${part.executableCode.code}`)
+      .update(
+        `exec:${part.executableCode.language}:${part.executableCode.code}`,
+      )
       .digest('hex');
     id = `exec_${contentHash}_${turnSalt}_${partIdx}`;
   } else if (isCodeExecutionResultPart(part)) {
     contentHash = createHash('sha256')
-      .update(`result:${part.codeExecutionResult.output}`)
+      .update(
+        `result:${part.codeExecutionResult.outcome}:${part.codeExecutionResult.output}`,
+      )
       .digest('hex');
     id = `result_${contentHash}_${turnSalt}_${partIdx}`;
   }

packages/core/src/context/utils/snapshotGenerator.ts

@@ -94,13 +94,36 @@ export const SnapshotStateHelper = {
       return {};
     }
 
+    // Flatten abstractsIds to ensure only pristine/replayable IDs are persisted.
+    // This prevents deep nesting of synthetic snapshot IDs which cannot be reconstructed
+    // from saved chat messages during session resume.
+    const nodeMap = new Map<string, ConcreteNode>();
+    for (const n of nodes) nodeMap.set(n.id, n);
+
+    const pristineIds = new Set<string>();
+    const toExpand = [...baseline.abstractsIds];
+    const seen = new Set<string>();
+
+    while (toExpand.length > 0) {
+      const id = toExpand.pop()!;
+      if (seen.has(id)) continue;
+      seen.add(id);
+
+      const node = nodeMap.get(id);
+      if (node?.abstractsIds && node.abstractsIds.length > 0) {
+        toExpand.push(...node.abstractsIds);
+      } else {
+        pristineIds.add(id);
+      }
+    }
+
     debugLogger.log(
-      `[SnapshotStateHelper] exportState: Exporting snapshot ID ${baseline.id} representing ${baseline.abstractsIds.length} consumed nodes.`,
+      `[SnapshotStateHelper] exportState: Exporting snapshot ID ${baseline.id} representing ${pristineIds.size} pristine nodes.`,
     );
     return {
       snapshot: {
         text: baseline.text,
-        consumedIds: baseline.abstractsIds,
+        consumedIds: Array.from(pristineIds),
         timestamp: baseline.timestamp,
       },
     };
@@ -124,7 +147,7 @@ export const SnapshotStateHelper = {
       inbox.publish('PROPOSED_SNAPSHOT', {
         newText: state.snapshot.text,
         consumedIds: state.snapshot.consumedIds,
-        type: 'accumulate',
+        type: 'restored',
         timestamp: state.snapshot.timestamp ?? Date.now(),
       });
     } else {

packages/core/src/core/fakeContentGenerator.ts

@@ -58,10 +58,14 @@ export class FakeContentGenerator implements ContentGenerator {
   userTierName?: string;
   paidTier?: GeminiUserTier;
 
+  private readonly responses: FakeResponse[];
+
   constructor(
-    private readonly responses: FakeResponse[],
+    responses: FakeResponse[],
     private readonly options: FakeContentGeneratorOptions = {},
-  ) {}
+  ) {
+    this.responses = structuredClone(responses);
+  }
 
   static async fromFile(
     filePath: string,

packages/core/src/services/chatRecordingService.ts

@@ -276,6 +276,7 @@ export async function loadConversationRecord(
       memoryScratchpad: metadata.memoryScratchpad,
       directories: metadata.directories,
       kind: metadata.kind,
+      contextState: metadata.contextState,
       messages: options?.metadataOnly ? [] : loadedMessages,
       messageCount: options?.metadataOnly
         ? metadataMessages.length || messageIds.length