feat(core): add project-level memory scope to save_memory tool (#24161)

packages/core/src/config/config.test.ts

@@ -227,6 +227,7 @@ vi.mock('../services/contextManager.js', () => ({
     getGlobalMemory: vi.fn().mockReturnValue(''),
     getExtensionMemory: vi.fn().mockReturnValue(''),
     getEnvironmentMemory: vi.fn().mockReturnValue(''),
+    getUserProjectMemory: vi.fn().mockReturnValue(''),
     getLoadedPaths: vi.fn().mockReturnValue(new Set()),
   })),
 }));
@@ -2948,6 +2949,7 @@ describe('Config JIT Initialization', () => {
       getEnvironmentMemory: vi
         .fn()
         .mockReturnValue('Environment Memory\n\nMCP Instructions'),
+      getUserProjectMemory: vi.fn().mockReturnValue(''),
       getLoadedPaths: vi.fn().mockReturnValue(new Set(['/path/to/GEMINI.md'])),
     } as unknown as ContextManager;
     (ContextManager as unknown as Mock).mockImplementation(
@@ -2975,6 +2977,7 @@ describe('Config JIT Initialization', () => {
       global: 'Global Memory',
       extension: 'Extension Memory',
       project: 'Environment Memory\n\nMCP Instructions',
+      userProjectMemory: '',
     });
 
     // Tier 1: system instruction gets only global memory

packages/core/src/config/config.ts

@@ -2282,6 +2282,7 @@ export class Config implements McpContext, AgentLoopContext {
         global: this.contextManager.getGlobalMemory(),
         extension: this.contextManager.getExtensionMemory(),
         project: this.contextManager.getEnvironmentMemory(),
+        userProjectMemory: this.contextManager.getUserProjectMemory(),
       };
     }
     return this.userMemory;
@@ -2311,13 +2312,20 @@ export class Config implements McpContext, AgentLoopContext {
 
   /**
    * Returns memory for the system instruction.
-   * When JIT is enabled, only global memory (Tier 1) goes in the system
-   * instruction. Extension and project memory (Tier 2) are placed in the
-   * first user message instead, per the tiered context model.
+   * When JIT is enabled, global memory and user project memory (Tier 1) go
+   * in the system instruction. Extension and project memory (Tier 2) are
+   * placed in the first user message instead, per the tiered context model.
+   * User project memory is in Tier 1 so mid-session saves are reflected
+   * via system instruction updates.
    */
   getSystemInstructionMemory(): string | HierarchicalMemory {
     if (this.experimentalJitContext && this.contextManager) {
-      return this.contextManager.getGlobalMemory();
+      const global = this.contextManager.getGlobalMemory();
+      const userProjectMemory = this.contextManager.getUserProjectMemory();
+      if (userProjectMemory?.trim()) {
+        return { global, userProjectMemory };
+      }
+      return global;
     }
     return this.userMemory;
   }
@@ -3476,7 +3484,7 @@ export class Config implements McpContext, AgentLoopContext {
     );
     if (!this.isMemoryManagerEnabled()) {
       maybeRegister(MemoryTool, () =>
-        registry.registerTool(new MemoryTool(this.messageBus)),
+        registry.registerTool(new MemoryTool(this.messageBus, this.storage)),
       );
     }
     maybeRegister(WebSearchTool, () =>

packages/core/src/config/memory.ts

@@ -8,6 +8,7 @@ export interface HierarchicalMemory {
   global?: string;
   extension?: string;
   project?: string;
+  userProjectMemory?: string;
 }
 
 /**
@@ -21,6 +22,12 @@ export function flattenMemory(memory?: string | HierarchicalMemory): string {
   if (memory.global?.trim()) {
     sections.push({ name: 'Global', content: memory.global.trim() });
   }
+  if (memory.userProjectMemory?.trim()) {
+    sections.push({
+      name: 'User Project Memory',
+      content: memory.userProjectMemory.trim(),
+    });
+  }
   if (memory.extension?.trim()) {
     sections.push({ name: 'Extension', content: memory.extension.trim() });
   }

packages/core/src/config/storage.test.ts

@@ -147,6 +147,17 @@ describe('Storage – additional helpers', () => {
     expect(storage.getProjectAgentsDir()).toBe(expected);
   });
 
+  it('getProjectMemoryDir returns ~/.gemini/memory/<identifier>', async () => {
+    await storage.initialize();
+    const expected = path.join(
+      os.homedir(),
+      GEMINI_DIR,
+      'memory',
+      PROJECT_SLUG,
+    );
+    expect(storage.getProjectMemoryDir()).toBe(expected);
+  });
+
   it('getMcpOAuthTokensPath returns ~/.gemini/mcp-oauth-tokens.json', () => {
     const expected = path.join(
       os.homedir(),

packages/core/src/config/storage.ts

@@ -266,6 +266,11 @@ export class Storage {
     return path.join(historyDir, identifier);
   }
 
+  getProjectMemoryDir(): string {
+    const identifier = this.getProjectIdentifier();
+    return path.join(Storage.getGlobalGeminiDir(), 'memory', identifier);
+  }
+
   getWorkspaceSettingsPath(): string {
     return path.join(this.getGeminiDir(), 'settings.json');
   }