feat(agent-core-v2): announce date changes via a system reminder

packages/agent-core-v2/docs/state-manifest.d.ts

@@ -23,7 +23,7 @@
 // references become '(circular)', and class instances collapse to a '(ClassName)'
 // marker — the wire shape of an entry is the JSON projection of the type here.
 //
-// Index (App: 0 keys · Workspace: 6 keys · Session: 18 keys · Agent: 69 keys)
+// Index (App: 0 keys · Workspace: 6 keys · Session: 18 keys · Agent: 70 keys)
 //   App
 //   Workspace
 //     workspaceDirs.ephemeralDirs          src/workspace/workspaceDirs/workspaceDirsService.ts
@@ -62,6 +62,7 @@
 //     agentsMdReminder.seeded                         src/agent/agentsMdReminder/agentsMdReminderService.ts
 //     contextInjector.isNewTurn                       src/agent/contextInjector/contextInjectorService.ts
 //     contextProjector.lastRepairSignature            src/agent/contextProjector/contextProjectorService.ts
+//     dateChange.seed                                 src/agent/dateChange/dateChangeService.ts
 //     externalHooks.stopHookContinuationUsed          src/agent/externalHooks/externalHooksService.ts
 //     fullCompaction.activeTurnId                     src/agent/fullCompaction/fullCompactionService.ts
 //     fullCompaction.compactionCountInTurn            src/agent/fullCompaction/fullCompactionService.ts
@@ -734,6 +735,12 @@ export interface AgentStateSnapshot {
         readonly kind: 'injection';
         readonly variant: string;
         readonly ownerPromptId?: string;
+        readonly disclosure?: /* ContextInjectionDisclosure — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
+          readonly kind: 'date';
+          readonly renderGeneration: number;
+          readonly localDate: string;
+          readonly timeZone: string;
+        };
       } | /* ShellCommandOrigin — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
         readonly kind: 'shell_command';
         readonly phase: 'input' | 'output';
@@ -858,6 +865,12 @@ export interface AgentStateSnapshot {
       readonly kind: 'injection';
       readonly variant: string;
       readonly ownerPromptId?: string;
+      readonly disclosure?: /* ContextInjectionDisclosure — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
+        readonly kind: 'date';
+        readonly renderGeneration: number;
+        readonly localDate: string;
+        readonly timeZone: string;
+      };
     } | /* ShellCommandOrigin — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
       readonly kind: 'shell_command';
       readonly phase: 'input' | 'output';
@@ -914,6 +927,12 @@ export interface AgentStateSnapshot {
         readonly kind: 'injection';
         readonly variant: string;
         readonly ownerPromptId?: string;
+        readonly disclosure?: /* ContextInjectionDisclosure — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
+          readonly kind: 'date';
+          readonly renderGeneration: number;
+          readonly localDate: string;
+          readonly timeZone: string;
+        };
       } | /* ShellCommandOrigin — packages/agent-core-v2/src/agent/contextMemory/types.ts */ {
         readonly kind: 'shell_command';
         readonly phase: 'input' | 'output';
@@ -980,6 +999,12 @@ export interface AgentStateSnapshot {
   'contextInjector.isNewTurn': boolean;
   // src/agent/contextProjector/contextProjectorService.ts
   'contextProjector.lastRepairSignature': string | null;
+  // src/agent/dateChange/dateChangeService.ts
+  'dateChange.seed': /* DateDisclosure — packages/agent-core-v2/src/agent/dateChange/dateChangeService.ts */ {
+    readonly localDate: string;
+    readonly timeZone: string;
+    readonly renderGeneration: number;
+  } | undefined;
   // src/agent/externalHooks/externalHooksService.ts
   'externalHooks.stopHookContinuationUsed': boolean;
   // src/agent/fullCompaction/fullCompactionService.ts

packages/agent-core-v2/docs/wire-manifest.d.ts

@@ -84,6 +84,12 @@ interface ConfigUpdatePayload {
   /** ThinkingEffort */
   thinkingLevel?: 'off' | 'on' | (string & {});
   systemPrompt?: string;
+  /** EnvironmentDisclosureSnapshot */
+  environmentDisclosure?: {
+    cwd: string;
+    date: { disclosed: true, value: { localDate: string, timeZone: string } } | { disclosed: false };
+  };
+  renderGeneration?: number;
   agentsMdPaths?: string[];
   disallowedTools?: string[];
 }
@@ -453,6 +459,12 @@ interface ProfileBindPayload {
   /** ThinkingEffort */
   thinkingEffort: 'off' | 'on' | (string & {});
   systemPrompt: string;
+  /** EnvironmentDisclosureSnapshot */
+  environmentDisclosure?: {
+    cwd: string;
+    date: { disclosed: true, value: { localDate: string, timeZone: string } } | { disclosed: false };
+  };
+  renderGeneration?: number;
   agentsMdPaths?: string[];
   activeToolNames?: string[];
   disallowedTools: string[];

packages/agent-core-v2/src/agent/contextInjector/contextInjector.ts

@@ -1,18 +1,30 @@
 import { createDecorator } from "#/_base/di/instantiation";
 import type { IDisposable } from "#/_base/di/lifecycle";
 import type { ContentPart } from "#/kosong/contract/message";
+import type { ContextInjectionDisclosure, ContextMessage } from '#/agent/contextMemory/types';
 
 export interface ContextInjectionContext {
   readonly injectedPositions: readonly number[];
   readonly lastInjectedAt: number | null;
+  readonly lastInjection?: ContextMessage;
+  readonly lastDisclosure?: ContextInjectionDisclosure;
   readonly isNewTurn: boolean;
 }
 
 export type ContextInjectionContent = string | readonly ContentPart[];
 
+export interface ContextInjectionResult {
+  readonly content: ContextInjectionContent;
+  readonly disclosure?: ContextInjectionDisclosure;
+}
+
 export type ContextInjectionProvider = (
   context: ContextInjectionContext,
-) => ContextInjectionContent | undefined | Promise<ContextInjectionContent | undefined>;
+) =>
+  | ContextInjectionContent
+  | ContextInjectionResult
+  | undefined
+  | Promise<ContextInjectionContent | ContextInjectionResult | undefined>;
 
 export interface IAgentContextInjectorService {
   readonly _serviceBrand: undefined;

packages/agent-core-v2/src/agent/contextInjector/contextInjectorService.ts

@@ -3,9 +3,12 @@
  *
  * Injects registered context providers through `loop` and `systemReminder`,
  * tracks their positions in `contextMemory` through `eventBus`, and reconciles
- * those positions after `wire` restoration. The plain-data `isNewTurn` flag is
- * registered into `agentState` (`IAgentStateService`) and read/written through
- * it; `entries` stays a plain instance field (its values hold provider
+ * those positions after `wire` restoration. Each provider call receives the
+ * newest surviving injection of its own variant (`lastInjection`) and the
+ * typed disclosure recorded on it (`lastDisclosure`), so providers never read
+ * context layout or position indexes themselves. The plain-data `isNewTurn`
+ * flag is registered into `agentState` (`IAgentStateService`) and read/written
+ * through it; `entries` stays a plain instance field (its values hold provider
  * functions, not plain data). Bound at Agent scope.
  */
 
@@ -22,7 +25,9 @@ import type { ContextMessage } from '#/agent/contextMemory/types';
 import { IWireService } from '#/wire/wire';
 import {
   IAgentContextInjectorService,
+  type ContextInjectionContent,
   type ContextInjectionProvider,
+  type ContextInjectionResult,
 } from './contextInjector';
 
 interface ContextInjectionEntry {
@@ -106,25 +111,41 @@ export class AgentContextInjectorService extends Disposable implements IAgentCon
   private async inject(): Promise<void> {
     const isNewTurn = this.isNewTurn;
     this.isNewTurn = false;
+    const history = this.context.get();
     for (const entry of this.entries) {
       const injectedPositions: readonly number[] = [...entry.positions];
+      const lastInjectedAt = injectedPositions.at(-1) ?? null;
+      const lastInjection = lastInjectedAt === null ? undefined : history[lastInjectedAt];
       const content = await entry.provider({
         injectedPositions,
-        lastInjectedAt: injectedPositions.at(-1) ?? null,
+        lastInjectedAt,
+        lastInjection,
+        lastDisclosure:
+          lastInjection?.origin?.kind === 'injection'
+            ? lastInjection.origin.disclosure
+            : undefined,
         isNewTurn,
       });
       if (!this.entries.has(entry)) continue;
       if (content === undefined) continue;
-      const origin = { kind: 'injection' as const, variant: entry.name };
-      if (typeof content === 'string') {
-        if (content.trim().length === 0) continue;
-        this.reminders.appendSystemReminder(content, origin);
+      const result: ContextInjectionResult =
+        typeof content === 'object' && content !== null && !Array.isArray(content)
+          ? (content as ContextInjectionResult)
+          : { content: content as ContextInjectionContent };
+      const origin = {
+        kind: 'injection' as const,
+        variant: entry.name,
+        disclosure: result.disclosure,
+      };
+      if (typeof result.content === 'string') {
+        if (result.content.trim().length === 0) continue;
+        this.reminders.appendSystemReminder(result.content, origin);
         continue;
       }
-      if (content.length === 0) continue;
+      if (result.content.length === 0) continue;
       this.context.append({
         role: 'user',
-        content: [...content],
+        content: [...result.content],
         toolCalls: [],
         origin,
       });

packages/agent-core-v2/src/agent/contextInjector/disclosureBaseline.ts

@@ -0,0 +1,38 @@
+/**
+ * `contextInjector` domain (L4) — disclosure-baseline helpers for reminder
+ * providers (currently `date_change`).
+ *
+ * A provider's baseline answers "what has the model already seen" from up to
+ * three sources, compared by render generation with ties won by the earlier
+ * argument: the typed disclosure on the provider's newest surviving
+ * in-context injection (newest in time on a tie, since the persisted floor
+ * never advances when a reminder fires), the persisted render-time floor, and
+ * a runtime seed recorded on first observation. Internal to the package; not
+ * part of the barrel export.
+ */
+
+import type { ContextInjectionDisclosure } from '#/agent/contextMemory/types';
+
+export function disclosureOfKind<K extends ContextInjectionDisclosure['kind']>(
+  disclosure: ContextInjectionDisclosure | undefined,
+  kind: K,
+): Extract<ContextInjectionDisclosure, { kind: K }> | undefined {
+  return disclosure?.kind === kind
+    ? (disclosure as Extract<ContextInjectionDisclosure, { kind: K }>)
+    : undefined;
+}
+
+export function pickDisclosureBaseline<T extends { readonly renderGeneration: number }>(
+  ...candidates: readonly (T | undefined)[]
+): T | undefined {
+  let winner: T | undefined;
+  for (const candidate of candidates) {
+    if (
+      candidate !== undefined &&
+      (winner === undefined || candidate.renderGeneration > winner.renderGeneration)
+    ) {
+      winner = candidate;
+    }
+  }
+  return winner;
+}

packages/agent-core-v2/src/agent/contextMemory/types.ts

@@ -34,8 +34,16 @@ export interface InjectionOrigin {
   readonly kind: 'injection';
   readonly variant: string;
   readonly ownerPromptId?: string;
+  readonly disclosure?: ContextInjectionDisclosure;
 }
 
+export type ContextInjectionDisclosure = {
+  readonly kind: 'date';
+  readonly renderGeneration: number;
+  readonly localDate: string;
+  readonly timeZone: string;
+};
+
 export interface ShellCommandOrigin {
   readonly kind: 'shell_command';
   readonly phase: 'input' | 'output';

packages/agent-core-v2/src/agent/dateChange/dateChange.ts

@@ -0,0 +1,16 @@
+/**
+ * `dateChange` domain (L4) — `IAgentDateChangeService` contract.
+ *
+ * Defines the Agent-scope marker service that announces calendar-date changes
+ * through a `date_change` context-injection reminder when a session outlives
+ * the date rendered into its system prompt.
+ */
+
+import { createDecorator, type ServiceIdentifier } from '#/_base/di/instantiation';
+
+export interface IAgentDateChangeService {
+  readonly _serviceBrand: undefined;
+}
+
+export const IAgentDateChangeService: ServiceIdentifier<IAgentDateChangeService> =
+  createDecorator<IAgentDateChangeService>('agentDateChangeService');