feat(agent-core-v2): remove the context budget reminders

.changeset/compaction-context-budget.md

@@ -2,4 +2,4 @@
 "@moonshot-ai/kimi-code": minor
 ---
 
-Remind the model of its context budget before automatic compaction, and after compaction point it at the session's event log for exact details.
+After compaction, point the model at the session's event log so it can recover exact details of the compacted conversation.

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

@@ -2,7 +2,6 @@ import type {
   CompactionResult,
   CompactionSource,
 } from './types';
-import type { CompactionTriggerBudget } from './strategy';
 import { createDecorator } from "#/_base/di/instantiation";
 import type { Event } from '#/_base/event';
 import type { Hooks } from '#/hooks';
@@ -12,10 +11,6 @@ export interface FullCompactionInput {
   readonly instruction?: string;
 }
 
-export interface CompactionBudget extends CompactionTriggerBudget {
-  readonly used: number;
-}
-
 export interface FullCompactionTask {
   readonly abortController: AbortController;
   readonly promise: Promise<CompactionResult>;
@@ -30,7 +25,6 @@ export interface IAgentFullCompactionService {
   readonly compacting: FullCompactionTask | null;
   begin(input: FullCompactionInput): boolean;
   cancel(): void;
-  budget(): CompactionBudget;
 
   readonly hooks: Hooks<{
     onWillCompact: FullCompactionTask;

packages/agent-core-v2/src/agent/fullCompaction/fullCompactionService.ts

@@ -26,10 +26,6 @@ import { stripDynamicToolContext } from '#/agent/toolSelect/dynamicTools';
 import { IAgentToolSelectService } from '#/agent/toolSelect/toolSelect';
 import { IAgentTodoService } from '#/features/todo/todoService';
 import { renderTodoList } from '#/features/todo/todoItem';
-import {
-  isContextBudgetReminder,
-  summarizeCompactionAheadFollowUp,
-} from '#/features/contextBudget/contextBudgetReminder';
 import { onUnexpectedError } from '#/_base/errors/unexpectedError';
 import type { WireLineRange } from '#/wire/record';
 import { IWireService } from '#/wire/wire';
@@ -52,7 +48,6 @@ import { renderCompactionInstruction } from './compactionInstruction';
 import { renderContextRecoveryPointer } from './contextRecovery';
 import {
   IAgentFullCompactionService,
-  type CompactionBudget,
   type FullCompactionInput,
   type FullCompactionTask,
 } from './fullCompaction';
@@ -248,10 +243,6 @@ export class AgentFullCompactionService extends Service implements IAgentFullCom
     return this._compacting;
   }
 
-  budget(): CompactionBudget {
-    return { used: this.tokenCountWithPending(), ...this.strategy.budget() };
-  }
-
   cancel(): void {
     const active = this._compacting;
     if (active !== null) {
@@ -652,9 +643,7 @@ export class AgentFullCompactionService extends Service implements IAgentFullCom
 
       const delays = retryBackoffDelays(MAX_COMPACTION_RETRY_ATTEMPTS);
       let attempt: CompactionAttemptResult | undefined;
-      let historyForModel: readonly ContextMessage[] = stripDynamicToolContext(originalHistory).filter(
-        (message) => !isContextBudgetReminder(message),
-      );
+      let historyForModel: readonly ContextMessage[] = stripDynamicToolContext(originalHistory);
       let droppedCount = 0;
       let overflowShrinkCount = 0;
       let emptyOrTruncatedShrinkCount = 0;
@@ -781,7 +770,6 @@ export class AgentFullCompactionService extends Service implements IAgentFullCom
         thinking_effort: thinkingEffort,
         trace_id: attempt.traceId,
         ...usageTelemetry(attempt.usage),
-        ...aheadReminderTelemetry(originalHistory),
       };
       this.telemetry.track2('compaction_finished', properties);
       return result;
@@ -845,29 +833,6 @@ export class AgentFullCompactionService extends Service implements IAgentFullCom
   }
 }
 
-type CompactionAheadTelemetryProperties = Pick<
-  CompactionFinishedEvent,
-  | 'ahead_reminder_delivered'
-  | 'ahead_steps_count'
-  | 'ahead_write_calls_count'
-  | 'ahead_bash_calls_count'
-  | 'ahead_todo_calls_count'
->;
-
-function aheadReminderTelemetry(
-  history: readonly ContextMessage[],
-): CompactionAheadTelemetryProperties {
-  const followUp = summarizeCompactionAheadFollowUp(history);
-  if (followUp === undefined) return { ahead_reminder_delivered: false };
-  return {
-    ahead_reminder_delivered: true,
-    ahead_steps_count: followUp.stepCount,
-    ahead_write_calls_count: followUp.writeCallCount,
-    ahead_bash_calls_count: followUp.bashCallCount,
-    ahead_todo_calls_count: followUp.todoCallCount,
-  };
-}
-
 function findAPIStatusError(error: unknown): APIStatusError | undefined {
   let current: unknown = error;
   const seen = new Set<unknown>();

packages/agent-core-v2/src/agent/fullCompaction/strategy.ts

@@ -27,17 +27,9 @@ export const DEFAULT_COMPACTION_CONFIG: CompactionConfig = {
   minOverflowReductionRatio: 0.05,
 };
 
-export interface CompactionTriggerBudget {
-  readonly maxSize: number;
-  readonly triggerRatio: number;
-  readonly reservedContextSize: number;
-  readonly triggerTokens: number;
-}
-
 export interface CompactionStrategy {
   shouldCompact(usedSize: number): boolean;
   shouldBlock(usedSize: number): boolean;
-  budget(): CompactionTriggerBudget;
   computeCompactCount(messages: readonly Message[], source: CompactionSource): number;
   reduceCompactOnOverflow(messages: readonly Message[]): number;
   readonly checkAfterStep: boolean;
@@ -59,10 +51,6 @@ export class RuntimeCompactionStrategy implements CompactionStrategy {
     return this.delegate().shouldBlock(usedSize);
   }
 
-  budget(): CompactionTriggerBudget {
-    return this.delegate().budget();
-  }
-
   computeCompactCount(messages: readonly Message[], source: CompactionSource): number {
     return this.windowDelegate().computeCompactCount(messages, source);
   }
@@ -141,24 +129,6 @@ export class DefaultCompactionStrategy implements CompactionStrategy {
     );
   }
 
-  budget(): CompactionTriggerBudget {
-    const maxSize = this.maxSize;
-    const reservedContextSize = this.config.reservedContextSize;
-    const reservedTrigger =
-      reservedContextSize > 0 && reservedContextSize < maxSize
-        ? maxSize - reservedContextSize
-        : Number.POSITIVE_INFINITY;
-    return {
-      maxSize,
-      triggerRatio: this.config.triggerRatio,
-      reservedContextSize,
-      triggerTokens:
-        maxSize <= 0
-          ? Number.POSITIVE_INFINITY
-          : Math.min(Math.ceil(maxSize * this.config.triggerRatio), reservedTrigger),
-    };
-  }
-
   private shouldUseReservedContext(usedSize: number): boolean {
     const reservedSize = this.config.reservedContextSize;
     return reservedSize > 0 && reservedSize < this.maxSize && usedSize + reservedSize >= this.maxSize;

packages/agent-core-v2/src/app/telemetry/events.ts

@@ -215,24 +215,6 @@ export interface CompactionFinishedEvent {
   input_cache_read?: number;
   input_cache_creation?: number;
   trace_id?: string;
-  ahead_reminder_delivered: boolean;
-  ahead_steps_count?: number;
-  ahead_write_calls_count?: number;
-  ahead_bash_calls_count?: number;
-  ahead_todo_calls_count?: number;
-}
-
-export interface ContextBudgetReminderEvent {
-  bucket: 'half' | 'three_quarters';
-  used_tokens: number;
-  trigger_tokens: number;
-  max_tokens: number;
-}
-
-export interface CompactionAheadReminderEvent {
-  used_tokens: number;
-  trigger_tokens: number;
-  lead_tokens: number;
 }
 
 export interface CompactionFailedEvent {
@@ -802,31 +784,6 @@ export const telemetryEventDefinitions = {
       input_cache_creation: 'Cache-creation input tokens',
       trace_id:
         'Trace id of the final compaction request round; absent for non-Kimi protocols',
-      ahead_reminder_delivered:
-        'Whether the compaction-ahead reminder had been delivered in the compacted window',
-      ahead_steps_count: 'Assistant steps taken between the compaction-ahead reminder and compaction',
-      ahead_write_calls_count: 'Write/Edit tool calls made after the compaction-ahead reminder',
-      ahead_bash_calls_count: 'Bash tool calls made after the compaction-ahead reminder',
-      ahead_todo_calls_count: 'Todo tool calls made after the compaction-ahead reminder',
-    },
-  }),
-  context_budget_reminder: defineAgentTelemetryEvent<ContextBudgetReminderEvent>({
-    owner: 'kimi-code',
-    comment: 'The model is told how much of its context budget is used, once per bucket.',
-    properties: {
-      bucket: 'Share of the compaction trigger reached: half or three_quarters',
-      used_tokens: 'Context tokens in use when the reminder was injected',
-      trigger_tokens: 'Token count at which automatic compaction triggers',
-      max_tokens: 'Effective context window size in tokens',
-    },
-  }),
-  compaction_ahead_reminder: defineAgentTelemetryEvent<CompactionAheadReminderEvent>({
-    owner: 'kimi-code',
-    comment: 'The model is warned once per window that automatic compaction is imminent.',
-    properties: {
-      used_tokens: 'Context tokens in use when the reminder was injected',
-      trigger_tokens: 'Token count at which automatic compaction triggers',
-      lead_tokens: 'Tokens between the reminder threshold and the compaction trigger',
     },
   }),
   compaction_failed: defineAgentTelemetryEvent<CompactionFailedEvent>({