diff --git a/README.md b/README.md
index 1e07094..3754d1e 100644
--- a/README.md
+++ b/README.md
@@ -145,12 +145,12 @@ On crash: Resume from last safe breakpoint, auto-seal incomplete tool calls
 ### 3. Fork & Trajectory Exploration
 
 ```typescript
-// Create a checkpoint at current state
-const checkpointId = await agent.checkpoint('before-decision');
+// Create a snapshot at current state
+const snapshotId = await agent.snapshot('before-decision');
 
 // Fork to explore different paths
-const explorerA = await agent.fork(checkpointId);
-const explorerB = await agent.fork(checkpointId);
+const explorerA = await agent.fork(snapshotId);
+const explorerB = await agent.fork(snapshotId);
 
 await explorerA.chat('Try approach A');
 await explorerB.chat('Try approach B');
diff --git a/docs/ROADMAP.md b/docs/ROADMAP.md
index ba00487..dd23b70 100644
--- a/docs/ROADMAP.md
+++ b/docs/ROADMAP.md
@@ -17,7 +17,7 @@
 | Multi-provider | Stable | Anthropic, OpenAI, Gemini, DeepSeek, Qwen, GLM... |
 | Tool System | Stable | Built-in + MCP protocol |
 | AgentPool | Stable | Up to 50 agents per process |
-| Checkpointer | Stable | Memory, File, Redis implementations |
+| Snapshot/Fork | Stable | Explore different agent trajectories |
 | Context Compression | Stable | Automatic history management |
 | Hook System | Stable | Pre/post model and tool hooks |
 
diff --git a/src/core/checkpointer.ts b/src/core/checkpointer.ts
deleted file mode 100644
index ef6baa7..0000000
--- a/src/core/checkpointer.ts
+++ /dev/null
@@ -1,164 +0,0 @@
-import type { Message, ToolCallRecord } from './types';
-import type { ToolDescriptor } from '../tools/registry';
-
-/**
- * Agent 状态快照
- */
-export interface AgentState {
-  status: 'ready' | 'working' | 'paused' | 'completed' | 'failed';
-  stepCount: number;
-  lastSfpIndex: number;
-  lastBookmark?: {
-    seq: number;
-    timestamp: number;
-  };
-}
-
-/**
- * Checkpoint 数据结构
- */
-export interface Checkpoint {
-  id: string;
-  agentId: string;
-  sessionId?: string;
-  timestamp: number;
-  version: string;
-
-  // Agent 状态
-  state: AgentState;
-  messages: Message[];
-  toolRecords: ToolCallRecord[];
-
-  // 工具恢复信息
-  tools: ToolDescriptor[];
-
-  // 配置
-  config: {
-    model: string;
-    systemPrompt?: string;
-    templateId?: string;
-  };
-
-  // 元数据
-  metadata: {
-    isForkPoint?: boolean;
-    parentCheckpointId?: string;
-    tags?: string[];
-    [key: string]: any;
-  };
-}
-
-/**
- * Checkpoint 元数据（列表时使用）
- */
-export interface CheckpointMetadata {
-  id: string;
-  agentId: string;
-  sessionId?: string;
-  timestamp: number;
-  isForkPoint?: boolean;
-  tags?: string[];
-}
-
-/**
- * Checkpointer 接口
- *
- * 提供可选的持久化机制，解耦 Store 强依赖
- */
-export interface Checkpointer {
-  /**
-   * 保存 checkpoint
-   */
-  save(checkpoint: Checkpoint): Promise<string>;
-
-  /**
-   * 加载 checkpoint
-   */
-  load(checkpointId: string): Promise<Checkpoint | null>;
-
-  /**
-   * 列出 Agent 的所有 checkpoints
-   */
-  list(
-    agentId: string,
-    options?: {
-      sessionId?: string;
-      limit?: number;
-      offset?: number;
-    }
-  ): Promise<CheckpointMetadata[]>;
-
-  /**
-   * 删除 checkpoint
-   */
-  delete(checkpointId: string): Promise<void>;
-
-  /**
-   * Fork checkpoint（可选）
-   */
-  fork?(checkpointId: string, newAgentId: string): Promise<string>;
-}
-
-/**
- * 内存 Checkpointer（默认实现）
- */
-export class MemoryCheckpointer implements Checkpointer {
-  private checkpoints = new Map<string, Checkpoint>();
-
-  async save(checkpoint: Checkpoint): Promise<string> {
-    this.checkpoints.set(checkpoint.id, JSON.parse(JSON.stringify(checkpoint)));
-    return checkpoint.id;
-  }
-
-  async load(checkpointId: string): Promise<Checkpoint | null> {
-    const checkpoint = this.checkpoints.get(checkpointId);
-    return checkpoint ? JSON.parse(JSON.stringify(checkpoint)) : null;
-  }
-
-  async list(
-    agentId: string,
-    options?: { sessionId?: string; limit?: number; offset?: number }
-  ): Promise<CheckpointMetadata[]> {
-    const allCheckpoints = Array.from(this.checkpoints.values())
-      .filter((cp) => cp.agentId === agentId)
-      .filter((cp) => !options?.sessionId || cp.sessionId === options.sessionId)
-      .sort((a, b) => b.timestamp - a.timestamp);
-
-    const start = options?.offset || 0;
-    const end = options?.limit ? start + options.limit : undefined;
-    const slice = allCheckpoints.slice(start, end);
-
-    return slice.map((cp) => ({
-      id: cp.id,
-      agentId: cp.agentId,
-      sessionId: cp.sessionId,
-      timestamp: cp.timestamp,
-      isForkPoint: cp.metadata.isForkPoint,
-      tags: cp.metadata.tags,
-    }));
-  }
-
-  async delete(checkpointId: string): Promise<void> {
-    this.checkpoints.delete(checkpointId);
-  }
-
-  async fork(checkpointId: string, newAgentId: string): Promise<string> {
-    const original = await this.load(checkpointId);
-    if (!original) {
-      throw new Error(`Checkpoint not found: ${checkpointId}`);
-    }
-
-    const forked: Checkpoint = {
-      ...original,
-      id: `${newAgentId}-${Date.now()}`,
-      agentId: newAgentId,
-      timestamp: Date.now(),
-      metadata: {
-        ...original.metadata,
-        parentCheckpointId: checkpointId,
-      },
-    };
-
-    return await this.save(forked);
-  }
-}
diff --git a/src/core/checkpointers/file.ts b/src/core/checkpointers/file.ts
deleted file mode 100644
index 6233297..0000000
--- a/src/core/checkpointers/file.ts
+++ /dev/null
@@ -1,135 +0,0 @@
-import { promises as fs } from 'fs';
-import * as path from 'path';
-import type { Checkpointer, Checkpoint, CheckpointMetadata } from '../checkpointer';
-
-/**
- * File-based Checkpointer
- *
- * 将 checkpoints 保存到本地文件系统
- */
-export class FileCheckpointer implements Checkpointer {
-  constructor(private readonly baseDir: string) {}
-
-  async save(checkpoint: Checkpoint): Promise<string> {
-    await this.ensureDir();
-    const agentDir = path.join(this.baseDir, checkpoint.agentId);
-    await fs.mkdir(agentDir, { recursive: true });
-
-    const filePath = path.join(agentDir, `${checkpoint.id}.json`);
-    await fs.writeFile(filePath, JSON.stringify(checkpoint, null, 2), 'utf-8');
-
-    return checkpoint.id;
-  }
-
-  async load(checkpointId: string): Promise<Checkpoint | null> {
-    try {
-      // 扫描所有 agent 目录查找 checkpoint
-      const agentDirs = await fs.readdir(this.baseDir);
-
-      for (const agentId of agentDirs) {
-        const agentDir = path.join(this.baseDir, agentId);
-        const stat = await fs.stat(agentDir);
-
-        if (!stat.isDirectory()) continue;
-
-        const filePath = path.join(agentDir, `${checkpointId}.json`);
-        try {
-          const content = await fs.readFile(filePath, 'utf-8');
-          return JSON.parse(content);
-        } catch {
-          continue;
-        }
-      }
-
-      return null;
-    } catch {
-      return null;
-    }
-  }
-
-  async list(
-    agentId: string,
-    options?: { sessionId?: string; limit?: number; offset?: number }
-  ): Promise<CheckpointMetadata[]> {
-    const agentDir = path.join(this.baseDir, agentId);
-
-    try {
-      const files = await fs.readdir(agentDir);
-      const checkpoints: CheckpointMetadata[] = [];
-
-      for (const file of files) {
-        if (!file.endsWith('.json')) continue;
-
-        const filePath = path.join(agentDir, file);
-        const content = await fs.readFile(filePath, 'utf-8');
-        const checkpoint: Checkpoint = JSON.parse(content);
-
-        if (options?.sessionId && checkpoint.sessionId !== options.sessionId) {
-          continue;
-        }
-
-        checkpoints.push({
-          id: checkpoint.id,
-          agentId: checkpoint.agentId,
-          sessionId: checkpoint.sessionId,
-          timestamp: checkpoint.timestamp,
-          isForkPoint: checkpoint.metadata.isForkPoint,
-          tags: checkpoint.metadata.tags,
-        });
-      }
-
-      // 按时间排序
-      checkpoints.sort((a, b) => b.timestamp - a.timestamp);
-
-      // 分页
-      const start = options?.offset || 0;
-      const end = options?.limit ? start + options.limit : undefined;
-
-      return checkpoints.slice(start, end);
-    } catch {
-      return [];
-    }
-  }
-
-  async delete(checkpointId: string): Promise<void> {
-    try {
-      const agentDirs = await fs.readdir(this.baseDir);
-
-      for (const agentId of agentDirs) {
-        const filePath = path.join(this.baseDir, agentId, `${checkpointId}.json`);
-        try {
-          await fs.unlink(filePath);
-          return;
-        } catch {
-          continue;
-        }
-      }
-    } catch {
-      // Ignore errors
-    }
-  }
-
-  async fork(checkpointId: string, newAgentId: string): Promise<string> {
-    const original = await this.load(checkpointId);
-    if (!original) {
-      throw new Error(`Checkpoint not found: ${checkpointId}`);
-    }
-
-    const forked: Checkpoint = {
-      ...original,
-      id: `${newAgentId}-${Date.now()}`,
-      agentId: newAgentId,
-      timestamp: Date.now(),
-      metadata: {
-        ...original.metadata,
-        parentCheckpointId: checkpointId,
-      },
-    };
-
-    return await this.save(forked);
-  }
-
-  private async ensureDir(): Promise<void> {
-    await fs.mkdir(this.baseDir, { recursive: true });
-  }
-}
diff --git a/src/core/checkpointers/index.ts b/src/core/checkpointers/index.ts
deleted file mode 100644
index fd1b026..0000000
--- a/src/core/checkpointers/index.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-export { MemoryCheckpointer } from '../checkpointer';
-export { FileCheckpointer } from './file';
-export { RedisCheckpointer } from './redis';
diff --git a/src/core/checkpointers/redis.ts b/src/core/checkpointers/redis.ts
deleted file mode 100644
index 3d20d51..0000000
--- a/src/core/checkpointers/redis.ts
+++ /dev/null
@@ -1,151 +0,0 @@
-import type { Checkpointer, Checkpoint, CheckpointMetadata } from '../checkpointer';
-
-/**
- * Redis 配置
- */
-export interface RedisCheckpointerConfig {
-  host?: string;
-  port?: number;
-  password?: string;
-  db?: number;
-  keyPrefix?: string;
-  ttl?: number; // TTL in seconds
-}
-
-/**
- * Redis-based Checkpointer
- *
- * 使用 Redis 存储 checkpoints（需要 ioredis）
- */
-export class RedisCheckpointer implements Checkpointer {
-  private redis: any;
-  private keyPrefix: string;
-  private ttl?: number;
-
-  constructor(config: RedisCheckpointerConfig = {}) {
-    this.keyPrefix = config.keyPrefix || 'kode:checkpoint:';
-    this.ttl = config.ttl;
-
-    // 延迟加载 ioredis（可选依赖）
-    try {
-      const Redis = require('ioredis');
-      this.redis = new Redis({
-        host: config.host || 'localhost',
-        port: config.port || 6379,
-        password: config.password,
-        db: config.db || 0,
-      });
-    } catch (error) {
-      throw new Error(
-        'ioredis is required for RedisCheckpointer. Install it with: npm install ioredis'
-      );
-    }
-  }
-
-  async save(checkpoint: Checkpoint): Promise<string> {
-    const key = this.getKey(checkpoint.id);
-    const value = JSON.stringify(checkpoint);
-
-    if (this.ttl) {
-      await this.redis.setex(key, this.ttl, value);
-    } else {
-      await this.redis.set(key, value);
-    }
-
-    // 添加到 agent 的索引
-    const indexKey = this.getIndexKey(checkpoint.agentId);
-    await this.redis.zadd(indexKey, checkpoint.timestamp, checkpoint.id);
-
-    return checkpoint.id;
-  }
-
-  async load(checkpointId: string): Promise<Checkpoint | null> {
-    const key = this.getKey(checkpointId);
-    const value = await this.redis.get(key);
-
-    if (!value) return null;
-
-    return JSON.parse(value);
-  }
-
-  async list(
-    agentId: string,
-    options?: { sessionId?: string; limit?: number; offset?: number }
-  ): Promise<CheckpointMetadata[]> {
-    const indexKey = this.getIndexKey(agentId);
-
-    // 按时间倒序获取 checkpoint IDs
-    const start = options?.offset || 0;
-    const end = options?.limit ? start + options.limit - 1 : -1;
-    const ids = await this.redis.zrevrange(indexKey, start, end);
-
-    const checkpoints: CheckpointMetadata[] = [];
-
-    for (const id of ids) {
-      const checkpoint = await this.load(id);
-      if (!checkpoint) continue;
-
-      if (options?.sessionId && checkpoint.sessionId !== options.sessionId) {
-        continue;
-      }
-
-      checkpoints.push({
-        id: checkpoint.id,
-        agentId: checkpoint.agentId,
-        sessionId: checkpoint.sessionId,
-        timestamp: checkpoint.timestamp,
-        isForkPoint: checkpoint.metadata.isForkPoint,
-        tags: checkpoint.metadata.tags,
-      });
-    }
-
-    return checkpoints;
-  }
-
-  async delete(checkpointId: string): Promise<void> {
-    const checkpoint = await this.load(checkpointId);
-    if (!checkpoint) return;
-
-    // 删除 checkpoint
-    const key = this.getKey(checkpointId);
-    await this.redis.del(key);
-
-    // 从索引中移除
-    const indexKey = this.getIndexKey(checkpoint.agentId);
-    await this.redis.zrem(indexKey, checkpointId);
-  }
-
-  async fork(checkpointId: string, newAgentId: string): Promise<string> {
-    const original = await this.load(checkpointId);
-    if (!original) {
-      throw new Error(`Checkpoint not found: ${checkpointId}`);
-    }
-
-    const forked: Checkpoint = {
-      ...original,
-      id: `${newAgentId}:${Date.now()}`,
-      agentId: newAgentId,
-      timestamp: Date.now(),
-      metadata: {
-        ...original.metadata,
-        parentCheckpointId: checkpointId,
-      },
-    };
-
-    return await this.save(forked);
-  }
-
-  async disconnect(): Promise<void> {
-    if (this.redis) {
-      await this.redis.quit();
-    }
-  }
-
-  private getKey(checkpointId: string): string {
-    return `${this.keyPrefix}${checkpointId}`;
-  }
-
-  private getIndexKey(agentId: string): string {
-    return `${this.keyPrefix}index:${agentId}`;
-  }
-}
diff --git a/src/index.ts b/src/index.ts
index 7e1bb3c..1609c8a 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -54,14 +54,6 @@ export {
   PermissionEvaluationContext,
   PermissionDecision,
 } from './core/permission-modes';
-export {
-  Checkpointer,
-  Checkpoint,
-  CheckpointMetadata,
-  AgentState,
-  MemoryCheckpointer,
-} from './core/checkpointer';
-export { FileCheckpointer, RedisCheckpointer } from './core/checkpointers';
 
 // Types
 export * from './core/types';
diff --git a/tests/README.md b/tests/README.md
index 7e411dd..0179eeb 100644
--- a/tests/README.md
+++ b/tests/README.md
@@ -108,7 +108,7 @@ export async function run() {
 - Scheduler & TimeBridge、MessageQueue、ContextManager、FilePool
 - 基础设施：JSONStore WAL、LocalSandbox 边界与危险命令拦截
 - 内置工具：文件、Bash、Todo 工具执行
-- 其他：Checkpointer、ToolRunner、AgentId 等辅助模块
+- 其他：ToolRunner、AgentId 等辅助模块
 
 ### 集成测试
 - 真实模型多轮对话与流式输出
diff --git a/tests/unit/core/checkpointer.test.ts b/tests/unit/core/checkpointer.test.ts
deleted file mode 100644
index b397c45..0000000
--- a/tests/unit/core/checkpointer.test.ts
+++ /dev/null
@@ -1,55 +0,0 @@
-import { MemoryCheckpointer, Checkpoint } from '../../../src/core/checkpointer';
-import { TestRunner, expect } from '../../helpers/utils';
-
-const runner = new TestRunner('Checkpointer');
-
-const baseCheckpoint: Checkpoint = {
-  id: 'cp-1',
-  agentId: 'agent-1',
-  timestamp: Date.now(),
-  version: '1',
-  state: { status: 'ready', stepCount: 0, lastSfpIndex: -1 },
-  messages: [],
-  toolRecords: [],
-  tools: [],
-  config: { model: 'mock' },
-  metadata: {},
-};
-
-runner
-  .test('保存、加载、列出和删除', async () => {
-    const cp = new MemoryCheckpointer();
-    await cp.save(baseCheckpoint);
-
-    const loaded = await cp.load('cp-1');
-    expect.toBeTruthy(loaded);
-
-    const list = await cp.list('agent-1');
-    expect.toEqual(list.length, 1);
-
-    await cp.delete('cp-1');
-    expect.toBeTruthy(await cp.load('cp-1') === null);
-  })
-
-  .test('fork 创建新快照', async () => {
-    const cp = new MemoryCheckpointer();
-    await cp.save(baseCheckpoint);
-
-    const forkId = await cp.fork('cp-1', 'agent-2');
-    expect.toBeTruthy(forkId);
-
-    const list = await cp.list('agent-2');
-    expect.toEqual(list.length, 1);
-    expect.toContain(list[0].id, 'agent-2');
-  });
-
-export async function run() {
-  return await runner.run();
-}
-
-if (require.main === module) {
-  run().catch((err) => {
-    console.error(err);
-    process.exitCode = 1;
-  });
-}