feat: 实用功能：/context 命令显示当前上下文窗口占用情况

README-en.md

@@ -75,6 +75,7 @@ Deep Code CLI supports agent skills that allow you to extend the assistant's cap
 | `/init`          | Initialize an AGENTS.md file (LLM project instructions) |
 | `/skills`        | List available skills                                   |
 | `/mcp`           | View MCP server status and available tools              |
+| `/context`       | View context window usage breakdown for the current session |
 | `/undo`          | Restore code and/or conversation to a previous point    |
 | `/exit`          | Quit (also `Ctrl+D` twice)                              |
 

README-zh_CN.md

@@ -74,6 +74,7 @@ Deep Code CLI 支持 agent skills，允许您扩展助手的能力：
 | `/init`     | 初始化 AGENTS.md 文件                 |
 | `/skills`   | 列出可用 skills                      |
 | `/mcp`      | 查看 MCP 服务器状态和可用工具                |
+| `/context`  | 查看当前会话的上下文窗口用量明细                 |
 | `/undo`     | 将代码和/或对话恢复到之前的状态                 |
 | `/exit`     | 退出（也可用连续 `Ctrl+D`）               |
 

README.md

@@ -74,6 +74,7 @@ Deep Code CLI 支持 agent skills，允许您扩展助手的能力：
 | `/init`     | 初始化 AGENTS.md 文件                 |
 | `/skills`   | 列出可用 skills                      |
 | `/mcp`      | 查看 MCP 服务器状态和可用工具                |
+| `/context`  | 查看当前会话的上下文窗口用量明细                 |
 | `/undo`     | 将代码和/或对话恢复到之前的状态                 |
 | `/exit`     | 退出（也可用连续 `Ctrl+D`）               |
 

src/session.ts

@@ -175,6 +175,28 @@ function getTotalTokens(usage: ModelUsage | null | undefined): number {
   return typeof totalTokens === "number" ? totalTokens : 0;
 }
 
+function estimateTokensFromText(text: string | null | undefined): number {
+  if (!text) return 0;
+  const total = [...text].length;
+  const cjk = text.match(/[㐀-鿿豈-﫿぀-ヿ가-힯]/gu)?.length ?? 0;
+  return Math.ceil(cjk + (total - cjk) / 4);
+}
+
+function estimateTokensFromUnknown(value: unknown): number {
+  if (value == null) return 0;
+  if (typeof value === "string") return estimateTokensFromText(value);
+  try {
+    return estimateTokensFromText(JSON.stringify(value));
+  } catch {
+    return 0;
+  }
+}
+
+// 各模型族的近似上下文窗口大小，仅用作进度条的分母。
+function getModelContextWindow(model: string): number {
+  return DEEPSEEK_V4_MODELS.has(model) ? 512 * 1024 : 128 * 1024;
+}
+
 export type SessionStatus =
   | "failed"
   | "pending"
@@ -235,6 +257,39 @@ export type SessionsIndex = {
   originalPath: string;
 };
 
+export type ContextCategoryKey =
+  | "system_prompt"
+  | "tool_definitions"
+  | "mcp_tools"
+  | "agent_instructions"
+  | "default_skills"
+  | "loaded_skills"
+  | "user_messages"
+  | "assistant_messages"
+  | "thinking"
+  | "tool_results";
+
+export type ContextCategoryUsage = {
+  key: ContextCategoryKey;
+  label: string;
+  tokens: number;
+};
+
+export type ContextStatus = {
+  model: string;
+  /** 来自最近一次 API 响应的权威活跃 token 数。 */
+  activeTokens: number;
+  /** 各分类估算 token 之和；让 UI 在尚未发起 API 调用时也能展示分项占比。 */
+  estimatedTotal: number;
+  /** 触发会话自动压缩（auto-compact）的阈值。 */
+  compactThreshold: number;
+  /** 当前模型的启发式上下文窗口大小（用作进度条的分母）。 */
+  contextWindow: number;
+  categories: ContextCategoryUsage[];
+  usagePerModel: Record<string, ModelUsage> | null;
+  messageCount: number;
+};
+
 export type SessionMessageRole = "system" | "user" | "assistant" | "tool";
 
 export type MessageMeta = {
@@ -363,6 +418,98 @@ export class SessionManager {
     return this.mcpManager.getStatus();
   }
 
+  getContextStatus(sessionId: string | null): ContextStatus {
+    const model = this.getResolvedSettings().model;
+    const compactThreshold = getCompactPromptTokenThreshold(model);
+    const contextWindow = getModelContextWindow(model);
+    const promptToolOptions = this.getPromptToolOptions();
+
+    const labels: Record<ContextCategoryKey, string> = {
+      system_prompt: "System prompt",
+      tool_definitions: "Built-in tools",
+      mcp_tools: "MCP tools",
+      agent_instructions: "Agent instructions (AGENTS.md)",
+      default_skills: "Default skills",
+      loaded_skills: "Loaded skills",
+      user_messages: "User messages",
+      assistant_messages: "Assistant replies",
+      thinking: "Thinking (reasoning)",
+      tool_results: "Tool results",
+    };
+    const tokens: Record<ContextCategoryKey, number> = {
+      system_prompt: 0,
+      tool_definitions: 0,
+      mcp_tools: 0,
+      agent_instructions: 0,
+      default_skills: 0,
+      loaded_skills: 0,
+      user_messages: 0,
+      assistant_messages: 0,
+      thinking: 0,
+      tool_results: 0,
+    };
+
+    // ── 静态（一次性）分类 —— 与会话状态无关 ─────────────────────────────────
+    tokens.system_prompt =
+      estimateTokensFromText(getSystemPrompt(this.projectRoot, promptToolOptions)) +
+      estimateTokensFromText(getRuntimeContext(this.projectRoot, promptToolOptions.model));
+    tokens.default_skills = estimateTokensFromText(getDefaultSkillPrompt());
+    tokens.agent_instructions = estimateTokensFromText(this.loadAgentInstructions());
+
+    // ── 工具定义（区分内置工具与 MCP 工具）─────────────────────────────────
+    const mcpToolNames = new Set(this.mcpToolDefinitions.map((t) => t.function.name));
+    for (const tool of getTools(promptToolOptions, this.mcpToolDefinitions)) {
+      const bucket = mcpToolNames.has(tool.function.name) ? "mcp_tools" : "tool_definitions";
+      tokens[bucket] += estimateTokensFromUnknown(tool);
+    }
+
+    // ── 会话消息 —— 按语义角色拆分 ────────────────────────────────────────
+    const messages = sessionId ? this.listSessionMessages(sessionId).filter((m) => !m.compacted) : [];
+    for (const message of messages) {
+      const params = message.messageParams as { tool_calls?: unknown; reasoning_content?: string } | null | undefined;
+      const contentTokens = estimateTokensFromText(message.content) + estimateTokensFromUnknown(message.contentParams);
+
+      if (message.meta?.skill) {
+        tokens.loaded_skills += contentTokens;
+        continue;
+      }
+      switch (message.role) {
+        case "system":
+          // 已计入 system_prompt / agent_instructions，此处跳过以避免重复计数。
+          break;
+        case "user":
+          tokens.user_messages += contentTokens;
+          break;
+        case "assistant":
+          tokens.assistant_messages += contentTokens + estimateTokensFromUnknown(params?.tool_calls);
+          tokens.thinking += estimateTokensFromText(params?.reasoning_content);
+          break;
+        case "tool":
+          tokens.tool_results += contentTokens;
+          break;
+      }
+    }
+
+    const categories: ContextCategoryUsage[] = (Object.keys(labels) as ContextCategoryKey[]).map((key) => ({
+      key,
+      label: labels[key],
+      tokens: tokens[key],
+    }));
+    const estimatedTotal = categories.reduce((sum, c) => sum + c.tokens, 0);
+    const session = sessionId ? this.getSession(sessionId) : null;
+
+    return {
+      model,
+      activeTokens: session?.activeTokens ?? 0,
+      estimatedTotal,
+      compactThreshold,
+      contextWindow,
+      categories,
+      usagePerModel: session?.usagePerModel ?? null,
+      messageCount: messages.length,
+    };
+  }
+
   async reconnectMcpServer(name: string, config?: McpServerConfig): Promise<void> {
     await this.mcpManager.reconnect(name, config);
     this.mcpToolDefinitions = this.mcpManager.getMcpToolDefinitions();

src/tests/session.test.ts

@@ -2906,6 +2906,131 @@ test("SessionManager.deleteSession does not affect other sessions", () => {
   assert.ok(messages.length > 0);
 });
 
+test("getContextStatus returns categories that sum to estimatedTotal", () => {
+  const workspace = createTempDir("deepcode-context-breakdown-");
+  const home = createTempDir("deepcode-context-home-");
+  setHomeDir(home);
+
+  const manager = new SessionManager({
+    projectRoot: workspace,
+    createOpenAIClient: () => ({ client: null, model: "test-model", thinkingEnabled: false }),
+    getResolvedSettings: () => ({ model: "test-model" }),
+    renderMarkdown: (text) => text,
+    onAssistantMessage: () => {},
+  });
+
+  const status = manager.getContextStatus(null);
+
+  // 没有会话时 → 会话相关分类应全部为 0，但静态开销
+  // （system prompt、tool 定义、运行时上下文）必须非 0。
+  const sumCategories = status.categories.reduce((sum, c) => sum + c.tokens, 0);
+  assert.equal(sumCategories, status.estimatedTotal);
+  assert.ok(status.estimatedTotal > 0, "static overhead should produce non-zero estimate");
+  assert.equal(status.activeTokens, 0);
+  assert.equal(status.messageCount, 0);
+
+  const userTokens = status.categories.find((c) => c.key === "user_messages")?.tokens ?? -1;
+  const builtinTokens = status.categories.find((c) => c.key === "tool_definitions")?.tokens ?? -1;
+  assert.equal(userTokens, 0);
+  assert.ok(builtinTokens > 0, "built-in tool definitions should contribute tokens");
+});
+
+test("getContextStatus threshold tracks model family", () => {
+  const workspace = createTempDir("deepcode-context-threshold-");
+  const home = createTempDir("deepcode-context-threshold-home-");
+  setHomeDir(home);
+
+  const defaultManager = new SessionManager({
+    projectRoot: workspace,
+    createOpenAIClient: () => ({ client: null, model: "deepseek-chat", thinkingEnabled: false }),
+    getResolvedSettings: () => ({ model: "deepseek-chat" }),
+    renderMarkdown: (text) => text,
+    onAssistantMessage: () => {},
+  });
+  const v4Manager = new SessionManager({
+    projectRoot: workspace,
+    createOpenAIClient: () => ({ client: null, model: "deepseek-v4-pro", thinkingEnabled: false }),
+    getResolvedSettings: () => ({ model: "deepseek-v4-pro" }),
+    renderMarkdown: (text) => text,
+    onAssistantMessage: () => {},
+  });
+
+  assert.equal(defaultManager.getContextStatus(null).compactThreshold, 128 * 1024);
+  assert.equal(v4Manager.getContextStatus(null).compactThreshold, 512 * 1024);
+  assert.ok(v4Manager.getContextStatus(null).contextWindow >= 512 * 1024);
+});
+
+test("getContextStatus attributes session messages to the right categories", () => {
+  const workspace = createTempDir("deepcode-context-msgs-");
+  const home = createTempDir("deepcode-context-msgs-home-");
+  setHomeDir(home);
+
+  const manager = new SessionManager({
+    projectRoot: workspace,
+    createOpenAIClient: () => ({ client: null, model: "test-model", thinkingEnabled: false }),
+    getResolvedSettings: () => ({ model: "test-model" }),
+    renderMarkdown: (text) => text,
+    onAssistantMessage: () => {},
+  });
+
+  const sessionId = createSessionAndMessages(manager, "ctx-session-1", "context test");
+  const projectDir = (manager as any).getProjectStorage().projectDir;
+  const messagePath = path.join(projectDir, `${sessionId}.jsonl`);
+  const now = new Date().toISOString();
+
+  // 追加：一条 user 消息、一条带 reasoning_content 的 assistant 消息，以及一条 tool 结果
+  const userMsg = {
+    id: "u-1",
+    sessionId,
+    role: "user",
+    content: "Please add a test for the new feature.",
+    contentParams: null,
+    messageParams: null,
+    compacted: false,
+    visible: true,
+    createTime: now,
+    updateTime: now,
+  };
+  const assistantMsg = {
+    id: "a-1",
+    sessionId,
+    role: "assistant",
+    content: "Sure, here's the plan.",
+    contentParams: null,
+    messageParams: { reasoning_content: "Step one: read the file. Step two: write a test." },
+    compacted: false,
+    visible: true,
+    createTime: now,
+    updateTime: now,
+  };
+  const toolMsg = {
+    id: "t-1",
+    sessionId,
+    role: "tool",
+    content: "file contents go here ".repeat(20),
+    contentParams: null,
+    messageParams: null,
+    compacted: false,
+    visible: false,
+    createTime: now,
+    updateTime: now,
+  };
+  fs.appendFileSync(
+    messagePath,
+    `${JSON.stringify(userMsg)}\n${JSON.stringify(assistantMsg)}\n${JSON.stringify(toolMsg)}\n`,
+    "utf8"
+  );
+
+  const status = manager.getContextStatus(sessionId);
+  const get = (key: string) => status.categories.find((c) => c.key === key)?.tokens ?? 0;
+
+  assert.ok(get("user_messages") > 0, "user message should contribute tokens");
+  assert.ok(get("assistant_messages") > 0, "assistant message should contribute tokens");
+  assert.ok(get("thinking") > 0, "reasoning_content should land in thinking bucket");
+  assert.ok(get("tool_results") > 0, "tool result should land in tool_results bucket");
+  assert.ok(status.messageCount >= 4, "expected the seeded messages plus the helper-created one");
+});
+
 /**
  * Helper: creates a session and writes a few messages to it so we can test
  * that deleteSession removes both the index entry and the messages file.

src/tests/slash-commands.test.ts

@@ -28,6 +28,7 @@ test("buildSlashCommands prefixes skills before built-ins", () => {
     "continue",
     "undo",
     "mcp",
+    "context",
     "raw",
     "exit",
   ]);

src/ui/core/slash-commands.ts

@@ -10,6 +10,7 @@ export type SlashCommandKind =
   | "continue"
   | "undo"
   | "mcp"
+  | "context"
   | "raw"
   | "exit";
 
@@ -71,6 +72,12 @@ export const BUILTIN_SLASH_COMMANDS: SlashCommandItem[] = [
     label: "/mcp",
     description: "Show MCP server status and available tools",
   },
+  {
+    kind: "context",
+    name: "context",
+    label: "/context",
+    description: "View context window usage breakdown for the current session",
+  },
   {
     kind: "raw",
     name: "raw",