diff --git a/vscode/src/codeReader/callTree/model.test.ts b/vscode/src/codeReader/callTree/model.test.ts
new file mode 100644
index 0000000..0821482
--- /dev/null
+++ b/vscode/src/codeReader/callTree/model.test.ts
@@ -0,0 +1,173 @@
+import type { CallEdge, CallRange, CallSymbol, CallTreeNode } from './model'
+import { describe, expect, it } from 'vitest'
+import { buildCallTrees } from './model'
+
+function symbol(name: string, line = 0, extra: Partial<CallSymbol> = {}): CallSymbol {
+  return {
+    uri: `file:///${name}`,
+    line,
+    character: 0,
+    name,
+    kind: 'function',
+    path: `${name}.py`,
+    ...extra,
+  }
+}
+
+function at(line: number, character = 0): CallRange {
+  return { line, character, endLine: line, endCharacter: character + 4 }
+}
+
+function edge(caller: CallSymbol, callee: CallSymbol, line: number, character = 0): CallEdge {
+  return { caller, callee, at: at(line, character) }
+}
+
+function currents(node: CallTreeNode): CallTreeNode[] {
+  return [...(node.current ? [node] : []), ...node.children.flatMap(currents)]
+}
+
+describe('调用边收成调用树', () => {
+  const mask = symbol('mask_phone', 27, { path: 'utils/phone.py' })
+
+  it('两个没有更上层调用者的根是两棵树，每棵记下当前块出现几次', () => {
+    const read = symbol('读取用户资料', 0, { path: 'routes/user.py' })
+    const profile = symbol('get_profile', 10, { path: 'services/user.py' })
+    const serialize = symbol('serialize_user', 20, { path: 'services/user.py' })
+    const load = symbol('load_user', 30, { path: 'services/user.py' })
+    const exp = symbol('导出通讯录', 0, { path: 'routes/export.py' })
+    const trees = buildCallTrees([
+      edge(serialize, mask, 40),
+      edge(load, mask, 50),
+      edge(profile, serialize, 12),
+      edge(profile, load, 14),
+      edge(read, profile, 3),
+      edge(exp, mask, 8),
+    ], mask)
+    expect(trees.map(tree => tree.name)).toEqual(['读取用户资料', '导出通讯录'])
+    expect(trees.map(tree => tree.hits)).toEqual([2, 1])
+    expect(trees[0].root.detail).toBe('入口')
+    expect(trees[0].root.where).toBe('routes/user.py:1')
+    expect(currents(trees[0].root).map(node => node.where)).toEqual(['utils/phone.py:28', 'utils/phone.py:28'])
+    expect(currents(trees[1].root)).toHaveLength(1)
+  })
+
+  it('同一个调用者的两段不同范围是当前块的两次出现', () => {
+    const caller = symbol('serialize_user', 20, { path: 'services/user.py' })
+    const root = symbol('读取用户资料', 0, { path: 'routes/user.py' })
+    const trees = buildCallTrees([
+      edge(caller, mask, 10),
+      edge(caller, mask, 20),
+      edge(root, caller, 3),
+    ], mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].hits).toBe(2)
+    const parent = trees[0].root.children[0]
+    expect(parent.name).toBe('serialize_user')
+    expect(parent.children.map(node => node.current)).toEqual([true, true])
+    expect(parent.otherCalls).toBeUndefined()
+  })
+
+  it('不在通向当前块的路径上的调用收成一行，不把那些符号画出来', () => {
+    const caller = symbol('serialize_user', 20, { path: 'services/user.py' })
+    const root = symbol('读取用户资料', 0, { path: 'routes/user.py' })
+    const trees = buildCallTrees([
+      edge(caller, mask, 10),
+      edge(caller, symbol('format_name'), 11),
+      edge(caller, symbol('format_name'), 12, 2),
+      edge(root, caller, 3),
+      edge(root, symbol('sideways'), 4),
+      edge(root, symbol('leftover'), 5),
+    ], mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].root.otherCalls).toBe(2)
+    expect(trees[0].root.children).toHaveLength(1)
+    expect(trees[0].root.children[0].otherCalls).toBe(2)
+    expect(trees[0].root.children[0].children.map(node => node.name)).toEqual(['mask_phone'])
+    const text = JSON.stringify(trees)
+    expect(text).not.toContain('format_name')
+    expect(text).not.toContain('sideways')
+    expect(text).not.toContain('leftover')
+  })
+
+  it('调用边绕回去就停，不把当前块再画到自己上面', () => {
+    const caller = symbol('get_profile')
+    const trees = buildCallTrees([
+      edge(caller, mask, 1),
+      edge(mask, caller, 2),
+    ], mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].name).toBe('get_profile')
+    expect(trees[0].root.children.map(node => node.name)).toEqual(['mask_phone'])
+    expect(trees[0].root.children[0].current).toBe(true)
+    expect(trees[0].root.children[0].children).toEqual([])
+    expect(trees[0].hits).toBe(1)
+  })
+
+  it('往上最多 8 层，再高的调用者不进这棵树', () => {
+    const above = Array.from({ length: 9 }, (_, index) => symbol(`n${index}`, index))
+    const edges = [edge(above[0], mask, 1)]
+    for (let index = 1; index < above.length; index++)
+      edges.push(edge(above[index], above[index - 1], index + 1))
+    const trees = buildCallTrees(edges, mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].name).toBe('n7')
+    expect(JSON.stringify(trees)).not.toContain('n8')
+  })
+
+  it('重复的同一段调用范围只算一次', () => {
+    const caller = symbol('serialize_user')
+    const trees = buildCallTrees([
+      edge(caller, mask, 10),
+      edge(caller, mask, 10),
+    ], mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].hits).toBe(1)
+  })
+
+  it('同一次查询里种类变了仍是同一个符号，不拆成两棵', () => {
+    const asFunction = symbol('get_profile', 4, { uri: 'file:///services/user.py', path: 'services/user.py', kind: 'function' })
+    const asClass = symbol('get_profile', 4, { uri: 'file:///services/user.py', path: 'services/user.py', kind: 'class' })
+    const trees = buildCallTrees([
+      edge(asFunction, mask, 8),
+      edge(asClass, mask, 8),
+    ], mask)
+    expect(trees).toHaveLength(1)
+    expect(trees[0].hits).toBe(1)
+    expect(trees[0].root.kind).toBe('function')
+  })
+
+  it('没有任何调用者就没有树', () => {
+    expect(buildCallTrees([], mask)).toEqual([])
+  })
+
+  it('选中的是类时，直接调用它的那一层是「新建」，类自己标当前，不编造方法', () => {
+    const order = symbol('OrderService', 13, { uri: 'file:///billing/order.py', path: 'billing/order.py', kind: 'class' })
+    const create = symbol('create_order', 20, { path: 'billing/order.py', detail: '创建一笔订单' })
+    const post = symbol('POST /orders', 0, { path: 'routes/order.py' })
+    const trees = buildCallTrees([
+      edge(create, order, 39),
+      edge(post, create, 5),
+      edge(create, symbol('charge'), 41),
+    ], order, { classTarget: true })
+    expect(trees).toHaveLength(1)
+    expect(trees[0].hits).toBe(1)
+    const created = trees[0].root.children[0]
+    expect(created.name).toBe('create_order')
+    expect(created.detail).toBe('创建一笔订单')
+    expect(created.otherCalls).toBe(1)
+    const made = created.children[0]
+    expect(made.name).toBe('新建 OrderService')
+    expect(made.detail).toBe('进入这个类')
+    expect(made.where).toBe('billing/order.py:40')
+    expect(made.current).toBe(false)
+    expect(made.kind).toBe('class')
+    expect(made.children).toEqual([{
+      name: 'OrderService',
+      kind: 'class',
+      where: 'billing/order.py:14',
+      current: true,
+      children: [],
+    }])
+    expect(JSON.stringify(trees)).not.toContain('方法')
+  })
+})
diff --git a/vscode/src/codeReader/callTree/model.ts b/vscode/src/codeReader/callTree/model.ts
new file mode 100644
index 0000000..cac96e0
--- /dev/null
+++ b/vscode/src/codeReader/callTree/model.ts
@@ -0,0 +1,215 @@
+/**
+ * 把调用边收成调用树。边从测试里喂，不碰编辑器。
+ * 身份是文件加名字起点；同一次查询里种类会变，种类只用来画图标。
+ */
+
+/** 往上走到第 8 层就停，这一层当作这棵树的根。 */
+export const CALL_TREE_MAX_DEPTH = 8
+
+/** 一个符号：文件、名字起点、给人看的路径和种类。 */
+export interface CallSymbol {
+  uri: string
+  /** 名字起点，行和列都从 0 起 */
+  line: number
+  character: number
+  name: string
+  /** 块种类，只决定图标，不参与认人 */
+  kind: string
+  /** 从工作区文件夹算起的路径 */
+  path: string
+  detail?: string
+}
+
+/** 调用出现的范围，在调用方文件里，行和列从 0 起。 */
+export interface CallRange {
+  line: number
+  character: number
+  endLine: number
+  endCharacter: number
+}
+
+/** 一次调用：谁在哪一段范围里调用了谁。同一段范围重复出现只算一次。 */
+export interface CallEdge {
+  caller: CallSymbol
+  callee: CallSymbol
+  at: CallRange
+}
+
+/** 树上的一个节点。当前块可以在同一棵里出现多次，每次一个节点。 */
+export interface CallTreeNode {
+  name: string
+  kind: string
+  /** 第二行。根是「入口」，新建类是「进入这个类」，其余是符号自己的说明（没有就不写） */
+  detail?: string
+  /** 文件:行，行从 1 起 */
+  where: string
+  current: boolean
+  children: CallTreeNode[]
+  /** 不在通向当前块的路径上的调用次数；没有就不画那一行 */
+  otherCalls?: number
+}
+
+/** 一棵调用树：根是没有更上层调用者的入口。 */
+export interface CallTree {
+  id: string
+  /** 入口的名字 */
+  name: string
+  /** 这一棵里当前块出现几次 */
+  hits: number
+  root: CallTreeNode
+}
+
+/** 文件加名字起点。种类不放进来。 */
+export function symbolKey(symbol: Pick<CallSymbol, 'uri' | 'line' | 'character'>): string {
+  return `${symbol.uri}#${symbol.line}:${symbol.character}`
+}
+
+function rangeKey(at: CallRange): string {
+  return `${at.line}:${at.character}-${at.endLine}:${at.endCharacter}`
+}
+
+function edgeKey(edge: CallEdge): string {
+  return `${symbolKey(edge.caller)}>${symbolKey(edge.callee)}@${rangeKey(edge.at)}`
+}
+
+function whereOf(symbol: CallSymbol): string {
+  return `${symbol.path}:${symbol.line + 1}`
+}
+
+/**
+ * 从目标往上收到根，再顺着走回目标。
+ * 不通向目标的调用不展开，记在父节点的 otherCalls 上。
+ * 选中的是类时，直接调用它的那一层写成「新建 类名」。
+ */
+export function buildCallTrees(edges: readonly CallEdge[], target: CallSymbol, options?: { classTarget?: boolean }): CallTree[] {
+  const symbols = new Map<string, CallSymbol>()
+  const remember = (symbol: CallSymbol): CallSymbol => {
+    const key = symbolKey(symbol)
+    const known = symbols.get(key)
+    if (known)
+      return known
+    symbols.set(key, symbol)
+    return symbol
+  }
+  const targetSymbol = remember(target)
+  const targetKey = symbolKey(targetSymbol)
+  const unique: CallEdge[] = []
+  const seen = new Set<string>()
+  for (const edge of edges) {
+    const normalized: CallEdge = { caller: remember(edge.caller), callee: remember(edge.callee), at: edge.at }
+    const key = edgeKey(normalized)
+    if (seen.has(key))
+      continue
+    seen.add(key)
+    unique.push(normalized)
+  }
+
+  const byCallee = new Map<string, CallEdge[]>()
+  const byCaller = new Map<string, CallEdge[]>()
+  for (const edge of unique) {
+    pushTo(byCallee, symbolKey(edge.callee), edge)
+    pushTo(byCaller, symbolKey(edge.caller), edge)
+  }
+  if ((byCallee.get(targetKey) ?? []).length === 0)
+    return []
+
+  const depthOf = new Map<string, number>()
+  const roots: CallSymbol[] = []
+  const rootSeen = new Set<string>()
+  const addRoot = (symbol: CallSymbol) => {
+    const key = symbolKey(symbol)
+    if (rootSeen.has(key))
+      return
+    rootSeen.add(key)
+    roots.push(symbol)
+  }
+  const climb = (node: CallSymbol, depth: number, path: ReadonlySet<string>) => {
+    const key = symbolKey(node)
+    const known = depthOf.get(key)
+    if (known !== undefined && known <= depth)
+      return
+    depthOf.set(key, depth)
+    if (depth >= CALL_TREE_MAX_DEPTH) {
+      addRoot(node)
+      return
+    }
+    const callers = new Map<string, CallSymbol>()
+    for (const edge of byCallee.get(key) ?? []) {
+      const callerKey = symbolKey(edge.caller)
+      if (!path.has(callerKey) && !callers.has(callerKey))
+        callers.set(callerKey, edge.caller)
+    }
+    if (callers.size === 0) {
+      addRoot(node)
+      return
+    }
+    const nextPath = new Set(path)
+    nextPath.add(key)
+    for (const caller of callers.values())
+      climb(caller, depth + 1, nextPath)
+  }
+  climb(targetSymbol, 0, new Set())
+
+  const classTarget = options?.classTarget === true
+  const render = (node: CallSymbol, path: ReadonlySet<string>): CallTreeNode => {
+    const key = symbolKey(node)
+    const current = key === targetKey
+    const nodeDepth = depthOf.get(key) ?? 0
+    const children: CallTreeNode[] = []
+    let otherCalls = 0
+    if (!current) {
+      const nextPath = new Set(path)
+      nextPath.add(key)
+      for (const edge of byCaller.get(key) ?? []) {
+        const calleeKey = symbolKey(edge.callee)
+        if (nextPath.has(calleeKey))
+          continue
+        const calleeDepth = depthOf.get(calleeKey)
+        if (calleeDepth === undefined) {
+          otherCalls++
+          continue
+        }
+        if (calleeDepth >= nodeDepth)
+          continue
+        const child = classTarget && calleeKey === targetKey
+          ? {
+              name: `新建 ${targetSymbol.name}`,
+              kind: 'class',
+              detail: '进入这个类',
+              where: `${node.path}:${edge.at.line + 1}`,
+              current: false,
+              children: [render(edge.callee, nextPath)],
+            }
+          : render(edge.callee, nextPath)
+        children.push(child)
+      }
+    }
+    return {
+      name: node.name,
+      kind: node.kind,
+      ...(node.detail && { detail: node.detail }),
+      where: whereOf(node),
+      current,
+      children,
+      ...(otherCalls > 0 && { otherCalls }),
+    }
+  }
+
+  return roots.map((root) => {
+    const rendered = render(root, new Set())
+    rendered.detail = '入口'
+    return { id: symbolKey(root), name: root.name, hits: countCurrent(rendered), root: rendered }
+  })
+}
+
+function pushTo(map: Map<string, CallEdge[]>, key: string, edge: CallEdge): void {
+  const list = map.get(key)
+  if (list)
+    list.push(edge)
+  else
+    map.set(key, [edge])
+}
+
+function countCurrent(node: CallTreeNode): number {
+  return (node.current ? 1 : 0) + node.children.reduce((sum, child) => sum + countCurrent(child), 0)
+}
diff --git a/vscode/src/codeReader/callTree/query.ts b/vscode/src/codeReader/callTree/query.ts
new file mode 100644
index 0000000..7529656
--- /dev/null
+++ b/vscode/src/codeReader/callTree/query.ts
@@ -0,0 +1,141 @@
+/**
+ * 问编辑器的调用关系命令，收成调用边。
+ * 语言扩展不提供、或者这一轮已经作废，就当没有。
+ */
+
+import type { CallHierarchyIncomingCall, CallHierarchyItem, CallHierarchyOutgoingCall, TextDocument } from 'vscode'
+import type { CallEdge, CallRange, CallSymbol } from './model'
+import { commands, SymbolKind, workspace } from 'vscode'
+import { symbolKey } from './model'
+import { collectCallEdges } from './walk'
+
+/**
+ * 在 offset 这个名字起点上问调用关系。
+ * 先准备符号，再往上问谁调用了它；路径上的调用者再问它还调用了谁，用来收「另外 N 处」。
+ */
+export async function loadCallEdges(
+  document: TextDocument,
+  offset: number,
+  cancelled: () => boolean,
+): Promise<{ symbol: CallSymbol, edges: CallEdge[] } | undefined> {
+  if (cancelled())
+    return undefined
+  const position = document.positionAt(offset)
+  let prepared: CallHierarchyItem | CallHierarchyItem[] | null | undefined
+  try {
+    prepared = await commands.executeCommand('vscode.prepareCallHierarchy', document.uri, position)
+  }
+  catch {
+    return undefined
+  }
+  if (cancelled() || prepared == null)
+    return undefined
+  const items = (Array.isArray(prepared) ? prepared : [prepared]).filter(item => item)
+  if (items.length === 0)
+    return undefined
+
+  const vscodeItems = new Map<string, CallHierarchyItem>()
+  const remember = (item: CallHierarchyItem): CallSymbol => {
+    const symbol = toSymbol(item)
+    vscodeItems.set(symbolKey(symbol), item)
+    return symbol
+  }
+  const starts: CallSymbol[] = []
+  const seen = new Set<string>()
+  for (const item of items) {
+    const symbol = remember(item)
+    const key = symbolKey(symbol)
+    if (seen.has(key))
+      continue
+    seen.add(key)
+    starts.push(symbol)
+  }
+  const symbol = starts.find(item => item.line === position.line && item.character === position.character) ?? starts[0]!
+  const edges: CallEdge[] = []
+  for (const start of starts) {
+    if (cancelled())
+      return undefined
+    edges.push(...await collectCallEdges(start, incoming, outgoing, cancelled))
+  }
+  return cancelled() ? undefined : { symbol, edges }
+
+  async function incoming(node: CallSymbol) {
+    return hits(node, 'vscode.provideIncomingCalls', (call: CallHierarchyIncomingCall) => ({
+      from: remember(call.from),
+      ranges: call.fromRanges.map(toRange),
+    }))
+  }
+
+  async function outgoing(node: CallSymbol) {
+    return hits(node, 'vscode.provideOutgoingCalls', (call: CallHierarchyOutgoingCall) => ({
+      to: remember(call.to),
+      ranges: call.fromRanges.map(toRange),
+    }))
+  }
+
+  async function hits<T, R>(node: CallSymbol, command: string, map: (call: T) => R): Promise<R[]> {
+    const item = vscodeItems.get(symbolKey(node))
+    if (!item || cancelled())
+      return []
+    try {
+      const calls = await commands.executeCommand<T[]>(command, item)
+      return (calls ?? []).map(map)
+    }
+    catch {
+      return []
+    }
+  }
+}
+
+function toSymbol(item: CallHierarchyItem): CallSymbol {
+  const start = item.selectionRange.start
+  return {
+    uri: item.uri.toString(),
+    line: start.line,
+    character: start.character,
+    name: item.name,
+    kind: kindName(item.kind),
+    path: workspace.asRelativePath(item.uri),
+    ...(item.detail && { detail: item.detail }),
+  }
+}
+
+function toRange(range: CallHierarchyItem['range']): CallRange {
+  return {
+    line: range.start.line,
+    character: range.start.character,
+    endLine: range.end.line,
+    endCharacter: range.end.character,
+  }
+}
+
+/** 编辑器的符号种类换成块种类，只给图标用。 */
+function kindName(kind: SymbolKind): string {
+  switch (kind) {
+    case SymbolKind.Method:
+    case SymbolKind.Function:
+    case SymbolKind.Operator:
+      return 'function'
+    case SymbolKind.Class:
+    case SymbolKind.Struct:
+    case SymbolKind.Constructor:
+      return 'class'
+    case SymbolKind.Interface:
+    case SymbolKind.TypeParameter:
+      return 'type'
+    case SymbolKind.Enum:
+      return 'enum'
+    case SymbolKind.Field:
+      return 'field'
+    case SymbolKind.Variable:
+      return 'variable'
+    case SymbolKind.Constant:
+      return 'const'
+    case SymbolKind.Module:
+    case SymbolKind.Namespace:
+    case SymbolKind.Package:
+      return 'module'
+    default:
+      return 'function'
+  }
+}
diff --git a/vscode/src/codeReader/callTree/session.test.ts b/vscode/src/codeReader/callTree/session.test.ts
new file mode 100644
index 0000000..55e6e75
--- /dev/null
+++ b/vscode/src/codeReader/callTree/session.test.ts
@@ -0,0 +1,108 @@
+import type { CallEdge, CallSymbol } from './model'
+import type { CallTreeBlock, CallTreeSource } from './session'
+import { describe, expect, it } from 'vitest'
+import { CallTreeSession } from './session'
+
+function symbol(name: string): CallSymbol {
+  return { uri: `file:///${name}`, line: 0, character: 0, name, kind: 'function', path: `${name}.py` }
+}
+
+function block(anchor: string, kind: string, defines?: number, children: CallTreeBlock[] = []): CallTreeBlock {
+  return { anchor, kind, ...(defines !== undefined && { defines: { startIndex: defines } }), children }
+}
+
+describe('调用树棵数在文档发出去之后算', () => {
+  it('只给有名字起点的函数和类计数，没有调用者的不出现，嵌在里面的也算', async () => {
+    const mask = symbol('mask_phone')
+    const caller = symbol('get_profile')
+    const edges: CallEdge[] = [{
+      caller,
+      callee: mask,
+      at: { line: 1, character: 0, endLine: 1, endCharacter: 4 },
+    }]
+    let source: CallTreeSource | undefined = {
+      version: 3,
+      blocks: [
+        block('fn', 'function', 10),
+        block('no-name', 'function'),
+        block('stmt', 'statement', 4),
+        block('cls', 'class', 20, [block('inner', 'function', 30)]),
+        block('alone', 'function', 40),
+      ],
+      load: async (offset) => {
+        if (offset === 10)
+          return { symbol: mask, edges }
+        if (offset === 30)
+          return { symbol: symbol('inner'), edges: [{ caller, callee: symbol('inner'), at: edges[0].at }] }
+        return { symbol: symbol('nobody'), edges: [] }
+      },
+    }
+    const posted: { type: string, counts?: Record<string, number> }[] = []
+    const session = new CallTreeSession(message => posted.push(message), () => source)
+    session.refresh()
+    await viFlush()
+    expect(posted).toEqual([{ type: 'callTreeCounts', version: 3, counts: { fn: 1, inner: 1 } }])
+    source = undefined
+    session.dispose()
+  })
+
+  it('文档版本变了就丢掉还在跑的查询，不把旧结果发出去', async () => {
+    let release: (() => void) | undefined
+    const gate = new Promise<void>((resolve) => {
+      release = resolve
+    })
+    let version = 1
+    const source: CallTreeSource = {
+      get version() {
+        return version
+      },
+      blocks: [block('fn', 'function', 1)],
+      load: async () => {
+        await gate
+        return { symbol: symbol('mask_phone'), edges: [] }
+      },
+    }
+    const posted: unknown[] = []
+    const session = new CallTreeSession(message => posted.push(message), () => source)
+    session.refresh()
+    version = 2
+    session.refresh()
+    release!()
+    await viFlush()
+    expect(posted).toEqual([{ type: 'callTreeCounts', version: 2, counts: {} }])
+    session.dispose()
+  })
+
+  it('打开某一块时版本对不上不发，对得上就把这棵树发回去', async () => {
+    const mask = symbol('mask_phone')
+    const caller = symbol('get_profile')
+    const edge: CallEdge = { caller, callee: mask, at: { line: 2, character: 0, endLine: 2, endCharacter: 3 } }
+    const source: CallTreeSource = {
+      version: 4,
+      blocks: [block('fn', 'function', 1)],
+      load: async () => ({ symbol: mask, edges: [edge] }),
+    }
+    const posted: { type: string, version?: number, anchor?: string, trees?: { name: string }[] }[] = []
+    const session = new CallTreeSession(message => posted.push(message), () => source)
+    session.open(3, 'fn')
+    expect(posted).toEqual([])
+    session.refresh()
+    await viFlush()
+    posted.length = 0
+    session.open(4, 'fn')
+    expect(posted).toEqual([{
+      type: 'callTree',
+      version: 4,
+      anchor: 'fn',
+      name: 'mask_phone',
+      where: 'mask_phone.py:1',
+      trees: [expect.objectContaining({ name: 'get_profile', hits: 1 })],
+    }])
+    session.dispose()
+  })
+})
+
+async function viFlush(): Promise<void> {
+  await new Promise(resolve => setTimeout(resolve, 0))
+  await new Promise(resolve => setTimeout(resolve, 0))
+}
diff --git a/vscode/src/codeReader/callTree/session.ts b/vscode/src/codeReader/callTree/session.ts
new file mode 100644
index 0000000..6eca451
--- /dev/null
+++ b/vscode/src/codeReader/callTree/session.ts
@@ -0,0 +1,136 @@
+/**
+ * 文档发出去之后，在后台数每个函数、类落在几棵调用树里。
+ * 页面点开某一块时，把这一版已经收好的边收成树发回去。版本对不上就丢掉。
+ */
+
+import type { ExtensionToWebview } from '../editor/messages'
+import type { CallEdge, CallSymbol, CallTree } from './model'
+import { buildCallTrees } from './model'
+
+/** 页面上的一块里，数调用树用得到的那几项。 */
+export interface CallTreeBlock {
+  anchor: string
+  kind: string
+  defines?: { startIndex: number }
+  children?: readonly CallTreeBlock[]
+}
+
+/** 眼下这份文档，以及按名字起点去问调用关系。问的时候可以取消。 */
+export interface CallTreeSource {
+  version: number
+  blocks: readonly CallTreeBlock[]
+  load: (offset: number, cancelled: () => boolean) => Promise<{ symbol: CallSymbol, edges: CallEdge[] } | undefined>
+}
+
+interface Cached {
+  symbol: CallSymbol
+  edges: CallEdge[]
+  classTarget: boolean
+}
+
+/** 一份文档的调用树：旧的查询作废，不挡住第一次预览。 */
+export class CallTreeSession {
+  private generation = 0
+  private readonly cache = new Map<string, Cached>()
+  private pending: { version: number, anchor: string } | undefined
+  private scannedGeneration = -1
+
+  constructor(
+    private readonly post: (message: ExtensionToWebview) => void,
+    private readonly source: () => CallTreeSource | undefined,
+  ) {}
+
+  /** 停掉还在跑的查询。文档又改了、预览关掉时用。 */
+  cancel(): void {
+    this.generation++
+    this.cache.clear()
+  }
+
+  /** 按眼下这份文档重新数。先停掉上一轮。 */
+  refresh(): void {
+    this.cancel()
+    void this.scan(this.generation)
+  }
+
+  /** 页面要看某一块。不是这一版文档的不理；还没数完就等这一轮数完再发。 */
+  open(version: number, anchor: string): void {
+    const src = this.source()
+    if (!src || src.version !== version)
+      return
+    const cached = this.cache.get(anchor)
+    if (cached) {
+      this.postTree(version, anchor, cached)
+      return
+    }
+    this.pending = { version, anchor }
+    if (this.scannedGeneration === this.generation)
+      this.postEmpty(version, anchor)
+  }
+
+  dispose(): void {
+    this.cancel()
+  }
+
+  private async scan(generation: number): Promise<void> {
+    const src = this.source()
+    if (!src || generation !== this.generation)
+      return
+    const version = src.version
+    const counts: Record<string, number> = {}
+    for (const block of callBlocks(src.blocks)) {
+      if (generation !== this.generation || this.source()?.version !== version)
+        return
+      const loaded = await src.load(block.defines!.startIndex, () => generation !== this.generation)
+      if (generation !== this.generation || this.source()?.version !== version)
+        return
+      if (!loaded)
+        continue
+      const classTarget = block.kind === 'class'
+      const trees = buildCallTrees(loaded.edges, loaded.symbol, { classTarget })
+      if (trees.length === 0)
+        continue
+      const cached: Cached = { symbol: loaded.symbol, edges: loaded.edges, classTarget }
+      this.cache.set(block.anchor, cached)
+      counts[block.anchor] = trees.length
+      if (this.pending?.anchor === block.anchor && this.pending.version === version)
+        this.postTree(version, block.anchor, cached)
+    }
+    if (generation !== this.generation || this.source()?.version !== version)
+      return
+    this.scannedGeneration = generation
+    this.post({ type: 'callTreeCounts', version, counts })
+    if (this.pending && this.pending.version === version && !this.cache.has(this.pending.anchor))
+      this.postEmpty(version, this.pending.anchor)
+  }
+
+  private postTree(version: number, anchor: string, cached: Cached): void {
+    const trees: CallTree[] = buildCallTrees(cached.edges, cached.symbol, { classTarget: cached.classTarget })
+    this.post({
+      type: 'callTree',
+      version,
+      anchor,
+      name: cached.symbol.name,
+      where: `${cached.symbol.path}:${cached.symbol.line + 1}`,
+      trees,
+    })
+  }
+
+  private postEmpty(version: number, anchor: string): void {
+    this.post({ type: 'callTree', version, anchor, name: '', where: '', trees: [] })
+  }
+}
+
+/** 有名字起点的函数和类，含嵌在别的块里面的。 */
+function callBlocks(blocks: readonly CallTreeBlock[]): CallTreeBlock[] {
+  const found: CallTreeBlock[] = []
+  const walk = (list: readonly CallTreeBlock[]) => {
+    for (const block of list) {
+      if ((block.kind === 'function' || block.kind === 'class') && block.defines)
+        found.push(block)
+      if (block.children?.length)
+        walk(block.children)
+    }
+  }
+  walk(blocks)
+  return found
+}
diff --git a/vscode/src/codeReader/callTree/walk.test.ts b/vscode/src/codeReader/callTree/walk.test.ts
new file mode 100644
index 0000000..e784ae5
--- /dev/null
+++ b/vscode/src/codeReader/callTree/walk.test.ts
@@ -0,0 +1,101 @@
+import type { CallRange, CallSymbol } from './model'
+import { describe, expect, it } from 'vitest'
+import { collectCallEdges } from './walk'
+
+function symbol(name: string, kind = 'function'): CallSymbol {
+  return { uri: `file:///${name}`, line: 0, character: 0, name, kind, path: `${name}.py` }
+}
+
+function range(line: number, character = 0): CallRange {
+  return { line, character, endLine: line, endCharacter: character + 3 }
+}
+
+describe('顺着调用者往上收集调用边', () => {
+  it('有环就停，不再问已经走过的那个', async () => {
+    const target = symbol('mask_phone')
+    const caller = symbol('get_profile')
+    const asked: string[] = []
+    const edges = await collectCallEdges(target, async (node) => {
+      asked.push(node.name)
+      if (node.name === 'mask_phone')
+        return [{ from: caller, ranges: [range(1)] }]
+      return [{ from: target, ranges: [range(2)] }]
+    }, async () => [])
+    expect(asked).toEqual(['mask_phone', 'get_profile'])
+    expect(edges).toEqual([{ caller, callee: target, at: range(1) }])
+  })
+
+  it('往上最多问 8 层，第 9 层的调用者不再问', async () => {
+    const names = ['t', ...Array.from({ length: 9 }, (_, index) => `n${index}`)]
+    const asked: string[] = []
+    await collectCallEdges(symbol('t'), async (node) => {
+      asked.push(node.name)
+      const index = names.indexOf(node.name)
+      const next = names[index + 1]
+      return next ? [{ from: symbol(next), ranges: [range(index + 1)] }] : []
+    }, async () => [])
+    expect(asked).toEqual(['t', 'n0', 'n1', 'n2', 'n3', 'n4', 'n5', 'n6'])
+  })
+
+  it('重复的调用范围去掉，同一调用者的两段不同范围都留下', async () => {
+    const target = symbol('mask_phone')
+    const caller = symbol('serialize_user')
+    const edges = await collectCallEdges(target, async () => [{
+      from: caller,
+      ranges: [range(10), range(10), range(20)],
+    }], async () => [])
+    expect(edges.map(item => item.at.line)).toEqual([10, 20])
+  })
+
+  it('种类不同但名字起点相同的调用者是同一个人，只往上问一次', async () => {
+    const target = symbol('mask_phone')
+    const asFunction = symbol('get_profile', 'function')
+    const asClass = symbol('get_profile', 'class')
+    const asked: string[] = []
+    const edges = await collectCallEdges(target, async (node) => {
+      asked.push(`${node.name}:${node.kind}`)
+      if (node.name === 'mask_phone')
+        return [{ from: asFunction, ranges: [range(1)] }, { from: asClass, ranges: [range(1)] }]
+      return []
+    }, async () => [])
+    expect(asked.filter(item => item.startsWith('get_profile'))).toEqual(['get_profile:function'])
+    expect(edges).toHaveLength(1)
+  })
+
+  it('路径上的调用者还要问它调用了谁，不通向当前块的边也留下；当前块自己不再往下问', async () => {
+    const target = symbol('mask_phone')
+    const caller = symbol('serialize_user')
+    const side = symbol('format_name')
+    const outgoingAsked: string[] = []
+    const edges = await collectCallEdges(target, async (node) => {
+      if (node.name === 'mask_phone')
+        return [{ from: caller, ranges: [range(4)] }]
+      return []
+    }, async (node) => {
+      outgoingAsked.push(node.name)
+      return [
+        { to: target, ranges: [range(4)] },
+        { to: side, ranges: [range(8), range(8)] },
+      ]
+    })
+    expect(outgoingAsked).toEqual(['serialize_user'])
+    expect(edges).toEqual([
+      { caller, callee: target, at: range(4) },
+      { caller, callee: side, at: range(8) },
+    ])
+  })
+
+  it('取消之后不再问下一个人', async () => {
+    const target = symbol('mask_phone')
+    const caller = symbol('get_profile')
+    let stop = false
+    const asked: string[] = []
+    const edges = await collectCallEdges(target, async (node) => {
+      asked.push(node.name)
+      stop = true
+      return [{ from: caller, ranges: [range(1)] }]
+    }, async () => [], () => stop)
+    expect(asked).toEqual(['mask_phone'])
+    expect(edges).toEqual([])
+  })
+})
diff --git a/vscode/src/codeReader/callTree/walk.ts b/vscode/src/codeReader/callTree/walk.ts
new file mode 100644
index 0000000..9a015fe
--- /dev/null
+++ b/vscode/src/codeReader/callTree/walk.ts
@@ -0,0 +1,108 @@
+/**
+ * 从当前符号往上问调用者，收到没有更上层的入口为止。
+ * 问的动作由外面传入：测试喂假的，宿主去问编辑器命令。
+ */
+
+import type { CallEdge, CallRange, CallSymbol } from './model'
+import { CALL_TREE_MAX_DEPTH, symbolKey } from './model'
+
+/** 一个调用者，以及它里面每一处调用的范围。 */
+export interface IncomingHit {
+  from: CallSymbol
+  ranges: readonly CallRange[]
+}
+
+/** 一个被调用的符号，以及调用它的每一处范围。 */
+export interface OutgoingHit {
+  to: CallSymbol
+  ranges: readonly CallRange[]
+}
+
+/**
+ * 收集通向 start 的调用边，再加上这些调用者通向别处的边。
+ * 有环就停。往上最多 8 层。cancelled 变成真就停，已经收到的也不要了。
+ * start 自己不再往下问：它调用了谁不画在这棵树上。
+ */
+export async function collectCallEdges(
+  start: CallSymbol,
+  incoming: (node: CallSymbol) => Promise<readonly IncomingHit[] | undefined>,
+  outgoing: (node: CallSymbol) => Promise<readonly OutgoingHit[] | undefined>,
+  cancelled: () => boolean = () => false,
+): Promise<CallEdge[]> {
+  if (cancelled())
+    return []
+  const edges: CallEdge[] = []
+  const seen = new Set<string>()
+  const ancestors = new Map<string, CallSymbol>()
+  const walked = new Map<string, number>()
+  const startKey = symbolKey(start)
+
+  const add = (caller: CallSymbol, callee: CallSymbol, at: CallRange) => {
+    const edge: CallEdge = { caller, callee, at }
+    const key = `${symbolKey(caller)}>${symbolKey(callee)}@${at.line}:${at.character}-${at.endLine}:${at.endCharacter}`
+    if (seen.has(key))
+      return
+    seen.add(key)
+    edges.push(edge)
+  }
+
+  const walk = async (node: CallSymbol, depth: number, path: ReadonlySet<string>): Promise<void> => {
+    if (cancelled() || depth >= CALL_TREE_MAX_DEPTH)
+      return
+    const calls = await incoming(node) ?? []
+    if (cancelled())
+      return
+    const here = new Set(path)
+    here.add(symbolKey(node))
+    const next = new Map<string, CallSymbol>()
+    for (const call of calls) {
+      const key = symbolKey(call.from)
+      if (here.has(key))
+        continue
+      for (const at of uniqueRanges(call.ranges))
+        add(call.from, node, at)
+      if (key !== startKey && !ancestors.has(key))
+        ancestors.set(key, call.from)
+      if (!next.has(key))
+        next.set(key, call.from)
+    }
+    for (const [key, caller] of next) {
+      if (cancelled() || depth + 1 >= CALL_TREE_MAX_DEPTH)
+        continue
+      const known = walked.get(key)
+      if (known !== undefined && known <= depth + 1)
+        continue
+      walked.set(key, depth + 1)
+      await walk(caller, depth + 1, here)
+    }
+  }
+
+  await walk(start, 0, new Set())
+  if (cancelled())
+    return []
+  for (const ancestor of ancestors.values()) {
+    if (cancelled())
+      return []
+    const calls = await outgoing(ancestor) ?? []
+    if (cancelled())
+      return []
+    for (const call of calls) {
+      for (const at of uniqueRanges(call.ranges))
+        add(ancestor, call.to, at)
+    }
+  }
+  return cancelled() ? [] : edges
+}
+
+function uniqueRanges(ranges: readonly CallRange[]): CallRange[] {
+  const seen = new Set<string>()
+  const unique: CallRange[] = []
+  for (const range of ranges) {
+    const key = `${range.line}:${range.character}-${range.endLine}:${range.endCharacter}`
+    if (seen.has(key))
+      continue
+    seen.add(key)
+    unique.push(range)
+  }
+  return unique
+}
diff --git a/vscode/src/codeReader/editor/messages.ts b/vscode/src/codeReader/editor/messages.ts
index 9816cbf..48a2afb 100644
--- a/vscode/src/codeReader/editor/messages.ts
+++ b/vscode/src/codeReader/editor/messages.ts
@@ -5,6 +5,7 @@
 import type { ClaudeImage } from '../../cc/spawnClaude'
 import type { FileAttribute } from '../attributes'
 import type { BlockView } from '../blockView'
+import type { CallTree } from '../callTree/model'
 import type { DocumentDiff } from '../diff/previewDiff'
 import type { ShownName } from '../nameResolution'
 import type { ProfileChoice } from '../qa/askProfiles'
@@ -129,6 +130,8 @@ export interface StickyScrollSettings {
  * repoLinkBroken：这个仓库链接打不开。没有 symbol 是文件或目录没有；有 symbol 是文件在、这个符号没有；没有 path 是不带路径的引用找不到
  * repoLinkOpened：这个仓库链接打开了。路径在；带了 symbol 时这个符号也在；没有 path 是不带路径的引用找到了
  * repoImagesChecked：id 那次 checkRepoImages 的回答。src 是预览里能直接用的图片地址；没有 src 是文件不在
+ * callTreeCounts：version 这份文档里，每个函数、类落在几棵调用树里（只包括大于 0 的）。不是页面上这个版本的不理
+ * callTree：anchor 那块的调用树。trees 空着是没有调用它的地方。不是页面上这个版本的不理
  */
 export type ExtensionToWebview
   = | DocumentMessage
@@ -153,6 +156,8 @@ export type ExtensionToWebview
     | { type: 'repoLinkOpened', path?: string, symbol?: string }
     | { type: 'repoImagesChecked', id: number, images: { path: string, src?: string }[] }
     | { type: 'focusPathAsk' }
+    | { type: 'callTreeCounts', version: number, counts: Record<string, number> }
+    | { type: 'callTree', version: number, anchor: string, name: string, where: string, trees: CallTree[] }
 
 /**
  * edit：把 startLine..endLine 这几行整行替换成 text（扩展端给每行补回原来的缩进）
@@ -178,6 +183,7 @@ export type ExtensionToWebview
  *   没有 path 是不带路径的引用（`[Name]`、`[Class.member]`），按这份文件找 symbol（本文件定义的，再是导入的，见 symbolLinks.ts）
  * checkRepoLinks：预览里这批仓库路径问哪些文件或目录没有，这批不带路径的引用（symbols）问哪些找不到。id 标出是哪一次问
  * checkRepoImages：预览里这批仓库图片，问哪些文件在，在的要预览里能直接用的地址。id 标出是哪一次问
+ * openCallTree：打开 anchor 那块的调用树。version 是这块所在的文档版本，对不上就不查
  */
 export type WebviewToExtension
   = | { type: 'ready' }
@@ -201,3 +207,4 @@ export type WebviewToExtension
     | { type: 'openRepoLink', path?: string, symbol?: string }
     | { type: 'checkRepoLinks', id: number, paths: string[], symbols: string[] }
     | { type: 'checkRepoImages', id: number, paths: string[] }
+    | { type: 'openCallTree', version: number, anchor: string }
diff --git a/vscode/src/codeReader/editor/previewEditor.ts b/vscode/src/codeReader/editor/previewEditor.ts
index 98ce6ff..bb0624a 100644
--- a/vscode/src/codeReader/editor/previewEditor.ts
+++ b/vscode/src/codeReader/editor/previewEditor.ts
@@ -23,6 +23,8 @@ import { commands, EndOfLine, Position, Range, Uri, window, workspace, Workspace
 import { logger } from '../../logging/logger'
 import { webviewHtml, webviewUiRoot } from '../../webview/html'
 import { DocumentCallees } from '../calleeKinds'
+import { loadCallEdges } from '../callTree/query'
+import { CallTreeSession } from '../callTree/session'
 import { findBlock, rewriteBlockComment } from '../commentRewrite'
 import { PreviewDiff } from '../diff/previewDiff'
 import { blockReplacement } from '../editText'
@@ -187,6 +189,20 @@ class Preview {
   private readonly rewriteStops = new Map<string, AbortController>()
   /** 最近一次发出去的文档（版本、块树、源码）：问 AI 时按块的记号在里面找那块代码，对比基准变了时拿它重新比 */
   private sent: SentDocument | undefined
+  /** 函数、类落在几棵调用树里。文档发出去之后再数，不挡住第一次预览 */
+  private readonly callTrees = new CallTreeSession(
+    message => this.post(message),
+    () => {
+      if (!this.sent || this.sent.version !== this.document.version)
+        return undefined
+      return {
+        version: this.sent.version,
+        blocks: this.sent.blocks,
+        load: (offset, cancelled) => loadCallEdges(this.document, offset, cancelled),
+      }
+    },
+  )
+
   /** 最近一次发出去的文档里语言插件自己认得出的名字（LanguageAdapter.symbols）：语言扩展查不到定义、各处出现时用 */
   private symbols: { version: number, list: LocalSymbol[] } | undefined
   /** 最近一次发出去的文档里各条导入引进来的名字：注释里不带路径的引用按它找导入的定义 */
@@ -318,6 +334,7 @@ class Preview {
     if (!this.ready)
       return
     const request = ++this.latest
+    this.callTrees.cancel()
     if (pathPreviewOf(this.document.uri)) {
       this.sent = undefined
       const reveal = this.pendingReveal
@@ -359,6 +376,7 @@ class Preview {
       this.names.resolve(version, report => resolveNames(displayNames, message.blocks, this.nameSources(), report))
       this.lookups.resolve(version, session.requests(), this.lookupSources())
       this.callees.resolve(version, callees.requests(), offset => this.calleeKind(offset))
+      this.callTrees.refresh()
     }
   }
 
@@ -455,6 +473,7 @@ class Preview {
   }
 
   dispose(): void {
+    this.callTrees.dispose()
     this.rewriteAbort.abort()
     clearTimeout(this.timer)
     this.names.dispose()
@@ -608,6 +627,9 @@ class Preview {
       case 'checkRepoImages':
         await this.checkRepoImages(msg.id, msg.paths)
         return
+      case 'openCallTree':
+        this.callTrees.open(msg.version, msg.anchor)
+        return
       case 'occurrenceNavigation':
         this.owner.navigation.update(this, msg.available)
     }
diff --git a/vscode/webview-ui/src/codeReader/App.tsx b/vscode/webview-ui/src/codeReader/App.tsx
index 8413216..94be0f4 100644
--- a/vscode/webview-ui/src/codeReader/App.tsx
+++ b/vscode/webview-ui/src/codeReader/App.tsx
@@ -1,13 +1,14 @@
 import type { ReactElement } from 'react'
 import type { BlockTreeState } from './BlockTree'
 import type { NameMap, VersionNames } from './displayNames'
-import type { DocumentDiff, DocumentMessage, Excluded, Reveal } from './types'
+import type { BlockView, CallTree, DocumentDiff, DocumentMessage, Excluded, Reveal } from './types'
 import type { OccurrencePage } from './useOccurrences'
 import type { ViewState } from './viewState'
 import { TriangleAlert } from 'lucide-react'
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
 import { AskThread } from './AskThread'
 import { BlockLevel } from './BlockTree'
+import { CallTreeDialog } from './CallTreeDialog'
 import { DefinitionPeekPopup } from './DefinitionPeekPopup'
 import { DiffBar, NewFileBanner } from './DiffBar'
 import { changeStops, diffTree, foldUnchanged, openedByDiff } from './diffView'
@@ -42,6 +43,17 @@ function savedBlockModes(): BlockModes {
   return { editing, folds }
 }
 
+function blockKind(blocks: readonly BlockView[], anchor: string): string {
+  for (const block of blocks) {
+    if (block.anchor === anchor)
+      return block.kind
+    const inner = blockKind(block.children, anchor)
+    if (inner)
+      return inner
+  }
+  return ''
+}
+
 export function App(): ReactElement | null {
   // 先于下面发 ready 的那个 effect 挂上收消息：ready 后扩展端马上发问答
   const qa = useQa()
@@ -64,6 +76,18 @@ export function App(): ReactElement | null {
   const [diff, setDiff] = useState<DocumentDiff | null>(null)
   /** 收到消息时读眼下哪些块在编辑（消息回调只在挂载时注册一次） */
   const editing = useRef(view.editing)
+  /** 页面上这份文档的版本：调用树的回答不是这一版就丢掉 */
+  const docVersion = useRef<number | undefined>(undefined)
+  const [callCounts, setCallCounts] = useState<{ version: number, counts: Record<string, number> }>()
+  const [openCall, setOpenCall] = useState<{
+    anchor: string
+    version: number
+    status: 'loading' | 'ready'
+    name: string
+    where: string
+    kind: string
+    trees: CallTree[]
+  } | null>(null)
   /** 块树所在的页面内容：钉住卡片时在这里面量 */
   const content = useRef<HTMLDivElement>(null)
   // 解析失败的文档没有块，不标差异；删掉的块按块筛选同样藏
@@ -113,12 +137,29 @@ export function App(): ReactElement | null {
     const off = onMessage((msg) => {
       switch (msg.type) {
         case 'document':
+          docVersion.current = msg.version
           setDoc(msg)
           setNames(documentNames(msg.version, msg.names))
           setKeep(prev => keptWhileEditing(prev, editing.current))
+          setCallCounts(prev => prev?.version === msg.version ? prev : undefined)
+          setOpenCall(prev => prev?.version === msg.version ? prev : null)
           if (msg.reveal)
             setReveal(msg.reveal)
           return
+        case 'callTreeCounts':
+          if (msg.version !== docVersion.current)
+            return
+          setCallCounts({ version: msg.version, counts: msg.counts })
+          return
+        case 'callTree':
+          if (msg.version !== docVersion.current)
+            return
+          setOpenCall((prev) => {
+            if (!prev || prev.anchor !== msg.anchor || prev.version !== msg.version)
+              return prev
+            return { ...prev, status: 'ready', name: msg.name, where: msg.where, trees: msg.trees }
+          })
+          return
         case 'reveal':
           setReveal({ line: msg.line, definition: msg.definition })
           return
@@ -148,6 +189,12 @@ export function App(): ReactElement | null {
   }, [view])
 
   const onFocused = useCallback(() => setFocusId(null), [])
+  const onOpenCall = useCallback((anchor: string) => {
+    if (!doc)
+      return
+    setOpenCall({ anchor, version: doc.version, status: 'loading', name: '', where: '', kind: blockKind(doc.blocks, anchor) || 'function', trees: [] })
+    postMessage({ type: 'openCallTree', version: doc.version, anchor })
+  }, [doc])
   const kindNames = useMemo(() => new Map(doc?.attributes.find(attribute => attribute.id === 'kind')?.values.map(value => [value.id, value.name])), [doc])
   const kindName = useCallback((kind: string) => kindNames.get(kind) ?? kind, [kindNames])
   const tree = useMemo((): BlockTreeState | null => doc && {
@@ -178,7 +225,12 @@ export function App(): ReactElement | null {
     ...(changes && { diff: changes }),
     ...(folded && { folded }),
     onOpenRun: id => setOpenedRuns(prev => new Set([...prev, id])),
-  }, [doc, view, collapsed, filter, covered, kindName, focusId, onFocused, setFolded, rewrites, qa, changes, folded])
+    callTree: {
+      counts: callCounts?.version === doc.version ? new Map(Object.entries(callCounts.counts)) : new Map(),
+      ...(openCall?.version === doc.version && { openAnchor: openCall.anchor }),
+      onOpen: onOpenCall,
+    },
+  }, [doc, view, collapsed, filter, covered, kindName, focusId, onFocused, setFolded, rewrites, qa, changes, folded, callCounts, openCall, onOpenCall])
 
   if (!doc || !tree)
     return null
@@ -248,6 +300,16 @@ export function App(): ReactElement | null {
         </div>
         {sticky?.enabled && <StickyLines content={content} blocks={doc.blocks} settings={sticky} />}
         <DefinitionPeekPopup shown={peek.shown} onJump={peek.jump} />
+        {openCall && (
+          <CallTreeDialog
+            kind={openCall.kind}
+            name={openCall.name}
+            where={openCall.where}
+            status={openCall.status === 'loading' ? 'loading' : openCall.trees.length === 0 ? 'empty' : 'ready'}
+            trees={openCall.trees}
+            onClose={() => setOpenCall(null)}
+          />
+        )}
       </DisplayNameContext>
     </HighlightContext>
   )
diff --git a/vscode/webview-ui/src/codeReader/BlockTools.test.tsx b/vscode/webview-ui/src/codeReader/BlockTools.test.tsx
index fa9c5c2..c1e7af6 100644
--- a/vscode/webview-ui/src/codeReader/BlockTools.test.tsx
+++ b/vscode/webview-ui/src/codeReader/BlockTools.test.tsx
@@ -2,13 +2,14 @@ import { renderToStaticMarkup } from 'react-dom/server'
 import { describe, expect, it } from 'vitest'
 import { BlockTools } from './BlockTools'
 
-function render(editing: boolean, ask?: { asking: boolean }, rewrite?: { rewriting: boolean, fresh?: boolean }): string {
+function render(editing: boolean, ask?: { asking: boolean }, rewrite?: { rewriting: boolean, fresh?: boolean }, callTree?: { count: number }): string {
   return renderToStaticMarkup(
     <BlockTools
       editing={editing}
       onToggleEdit={() => {}}
       {...(ask && { asking: ask.asking, onToggleAsk: () => {} })}
       {...(rewrite && { rewrite: { rewriting: rewrite.rewriting, fresh: rewrite.fresh ?? false, onRewrite: () => {} } })}
+      {...(callTree && { callTree: { anchor: 'fn', count: callTree.count, open: false, onOpen: () => {} } })}
     />,
   )
 }
@@ -64,4 +65,17 @@ describe('块右上角的图标按钮', () => {
     expect(buttons[1]).toContain('data-tooltip="问 AI"')
     expect(buttons[2]).toContain('data-tooltip="编辑"')
   })
+
+  it('调用树棵数大于 0 时排在编辑后面，按钮上是这个数字；棵数是 0 不出现', () => {
+    const html = render(false, { asking: false }, { rewriting: false }, { count: 3 })
+    const buttons = [...html.matchAll(/<button[^>]*>/g)].map(match => match[0])
+    expect(buttons).toHaveLength(4)
+    expect(buttons[2]).toContain('data-tooltip="编辑"')
+    expect(buttons[3]).toContain('data-tooltip="调用树" aria-label="调用树"')
+    expect(buttons[3]).toContain('data-call-tree="fn"')
+    expect(visibleText(html)).toBe('3')
+    const hidden = render(false, { asking: false }, { rewriting: false }, { count: 0 })
+    expect(hidden).not.toContain('调用树')
+    expect(hidden.match(/<button/g)).toHaveLength(3)
+  })
 })
diff --git a/vscode/webview-ui/src/codeReader/BlockTools.tsx b/vscode/webview-ui/src/codeReader/BlockTools.tsx
index e6c0553..ceaeb7e 100644
--- a/vscode/webview-ui/src/codeReader/BlockTools.tsx
+++ b/vscode/webview-ui/src/codeReader/BlockTools.tsx
@@ -1,5 +1,5 @@
 import type { ReactElement } from 'react'
-import { Eye, MessageSquareText, Pencil, Sparkles } from 'lucide-react'
+import { Eye, GitBranch, MessageSquareText, Pencil, Sparkles } from 'lucide-react'
 
 /** 「重写注释」按钮的样子和动作：fresh 是块还没有注释、点了新写一段；正在重写时不能再点。 */
 export interface RewriteTool {
@@ -14,7 +14,7 @@ export interface RewriteTool {
  * 「问 AI」：点开 / 收起块下面的问答区，展开时带按下的底色。
  * 「编辑 / 预览」切换：预览时是铅笔「编辑」，编辑时是眼睛「预览」、带按下的底色。
  */
-export function BlockTools({ editing, onToggleEdit, asking, onToggleAsk, rewrite }: {
+export function BlockTools({ editing, onToggleEdit, asking, onToggleAsk, rewrite, callTree }: {
   editing: boolean
   onToggleEdit: () => void
   /** 块下面的问答区展开着 */
@@ -23,6 +23,8 @@ export function BlockTools({ editing, onToggleEdit, asking, onToggleAsk, rewrite
   onToggleAsk?: () => void
   /** 没给就不显示「按注释规范重写」（不能写注释的块） */
   rewrite?: RewriteTool
+  /** 没给，或棵数是 0，就不显示调用树（还没查到、没有调用者、语言不提供） */
+  callTree?: { anchor: string, count: number, open: boolean, onOpen: () => void }
 }): ReactElement {
   const label = editing ? '预览' : '编辑'
   const Icon = editing ? Eye : Pencil
@@ -65,6 +67,21 @@ export function BlockTools({ editing, onToggleEdit, asking, onToggleAsk, rewrite
       >
         <Icon size={14} strokeWidth={1.8} aria-hidden />
       </button>
+      {callTree && callTree.count > 0 && (
+        <button
+          type="button"
+          className="cr-tool flex h-5 items-center justify-center gap-px rounded px-1"
+          data-call-tree={callTree.anchor}
+          data-active={callTree.open ? '' : undefined}
+          data-tooltip="调用树"
+          aria-label="调用树"
+          aria-expanded={callTree.open}
+          onClick={callTree.onOpen}
+        >
+          <GitBranch size={14} strokeWidth={1.8} aria-hidden />
+          <span className="cr-call-count">{callTree.count}</span>
+        </button>
+      )}
     </div>
   )
 }
diff --git a/vscode/webview-ui/src/codeReader/BlockTree.tsx b/vscode/webview-ui/src/codeReader/BlockTree.tsx
index 1eaed89..1a4a66b 100644
--- a/vscode/webview-ui/src/codeReader/BlockTree.tsx
+++ b/vscode/webview-ui/src/codeReader/BlockTree.tsx
@@ -37,9 +37,18 @@ export interface EditTree {
   onStopRewrite: (anchor: string) => void
 }
 
+/** 函数、类落在几棵调用树里。定义浮窗不传，跟问 AI 一样不画这排按钮。 */
+export interface CallTreeTools {
+  counts: ReadonlyMap<string, number>
+  openAnchor?: string
+  onOpen: (anchor: string) => void
+}
+
 export interface BlockTreeState {
   /** 能编辑（页面上的块树）；定义卡片浮窗里没有 */
   edit?: EditTree
+  /** 调用树。只读的树不传 */
+  callTree?: CallTreeTools
   /** 眼下折叠着的块 id、属性行 id 和子行 id（propertyRowId、propertyItemId）：用户的选择叠在默认上，见 collapsedIds */
   collapsed: ReadonlySet<string>
   /** 按筛选不画的块（连同子孙），见 applyFilter */
@@ -227,6 +236,18 @@ function BlockPreview({ block, tree, marks }: { block: BlockView, tree: BlockTre
 }
 
 /** 这块的「重写注释」按钮，排在右上角那排按钮里：能写注释（commentTarget）、页面上能改代码时才有。 */
+function callTreeTool(block: BlockView, tree: BlockTreeState) {
+  const callTree = tree.callTree
+  if (!callTree || (block.kind !== 'function' && block.kind !== 'class'))
+    return undefined
+  return {
+    anchor: block.anchor,
+    count: callTree.counts.get(block.anchor) ?? 0,
+    open: callTree.openAnchor === block.anchor,
+    onOpen: () => callTree.onOpen(block.anchor),
+  }
+}
+
 function rewriteTool(block: BlockView, edit: EditTree | undefined): RewriteTool | undefined {
   if (!edit || !block.commentTarget)
     return undefined
@@ -319,6 +340,7 @@ function BlockCard({ block, tree }: { block: BlockView, tree: BlockTreeState }):
           asking={tree.qa?.state.open.includes(block.anchor)}
           onToggleAsk={tree.qa && (() => tree.qa?.onToggle(block.anchor))}
           rewrite={rewriteTool(block, edit)}
+          callTree={callTreeTool(block, tree)}
         />
       )}
     </div>
diff --git a/vscode/webview-ui/src/codeReader/CallTreeDialog.test.tsx b/vscode/webview-ui/src/codeReader/CallTreeDialog.test.tsx
new file mode 100644
index 0000000..2fe2da2
--- /dev/null
+++ b/vscode/webview-ui/src/codeReader/CallTreeDialog.test.tsx
@@ -0,0 +1,225 @@
+// @vitest-environment happy-dom
+
+import type { ReactElement } from 'react'
+import type { Root } from 'react-dom/client'
+import type { BlockTreeState } from './BlockTree'
+import type { BlockView, CallTree } from './types'
+import { act, useState } from 'react'
+import { createRoot } from 'react-dom/client'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import { BlockLevel } from './BlockTree'
+import { CallTreeDialog } from './CallTreeDialog'
+
+vi.mock('./useOccurrences', async () => {
+  const { createContext } = await import('react')
+  return { HighlightContext: createContext(undefined) }
+})
+vi.mock('./vscode', () => ({ postMessage: () => {}, onMessage: () => () => {}, viewState: { get: () => ({ editing: [], folds: {} }), update: () => {} } }))
+
+let container: HTMLDivElement
+let root: Root
+
+beforeEach(() => {
+  vi.stubGlobal('IS_REACT_ACT_ENVIRONMENT', true)
+  container = document.createElement('div')
+  document.body.append(container)
+  root = createRoot(container)
+})
+
+afterEach(async () => {
+  await act(async () => root.unmount())
+  container.remove()
+  vi.unstubAllGlobals()
+})
+
+async function render(element: ReactElement): Promise<void> {
+  await act(async () => root.render(element))
+}
+
+function block(kind: string, id = kind): BlockView {
+  return {
+    id,
+    anchor: id,
+    kind,
+    startLine: 0,
+    endLine: 1,
+    code: '',
+    codeTokens: [],
+    attributes: { kind },
+    concepts: [{ id: kind, label: kind, icon: kind === 'class' ? 'box' : 'braces' }],
+    children: [],
+    translation: [{ text: id, role: 'plain' }],
+  }
+}
+
+function tree(callTree?: BlockTreeState['callTree'], edit = true): BlockTreeState {
+  return {
+    ...(edit && {
+      edit: {
+        version: 1,
+        editing: new Set<string>(),
+        focusId: null,
+        onFocused: () => {},
+        onToggleEdit: () => {},
+        rewrites: new Map(),
+        onRewriteComment: () => {},
+        onStopRewrite: () => {},
+      },
+    }),
+    collapsed: new Set(),
+    hidden: new Set(),
+    temporary: new Set(),
+    covered: new Map(),
+    kindName: kind => kind,
+    onToggleFold: () => {},
+    onSetFolds: () => {},
+    onOpenRun: () => {},
+    ...(callTree && { callTree }),
+  }
+}
+
+function node(name: string, extra: Partial<CallTree['root']> = {}): CallTree['root'] {
+  return { name, kind: 'function', where: `${name}.py:1`, current: false, children: [], ...extra }
+}
+
+const ONE: CallTree = {
+  id: 'one',
+  name: '夜间对账',
+  hits: 1,
+  root: node('夜间对账', { detail: '入口', children: [node('mask_phone', { current: true, where: 'utils/phone.py:28' })] }),
+}
+
+const MANY: CallTree[] = [
+  {
+    id: 'read',
+    name: '读取用户资料',
+    hits: 2,
+    root: node('读取用户资料', {
+      detail: '入口',
+      otherCalls: 2,
+      children: [node('mask_phone', { current: true }), node('mask_phone', { current: true })],
+    }),
+  },
+  ONE,
+]
+
+describe('调用树弹框', () => {
+  it('棵数为 0 的函数没有按钮，类有，语句没有；只读的树一排按钮都没有', async () => {
+    const counts = new Map([['function', 0], ['class', 2], ['statement', 4]])
+    await render(<BlockLevel blocks={[block('function'), block('class'), block('statement')]} tree={tree({ counts, onOpen: () => {} })} />)
+    expect(container.querySelector('[data-call-tree="function"]')).toBeNull()
+    expect(container.querySelector('[data-call-tree="statement"]')).toBeNull()
+    expect(container.querySelector('[data-call-tree="class"]')).not.toBeNull()
+    expect(container.querySelector('[data-call-tree="class"]')!.textContent).toBe('2')
+
+    await render(<BlockLevel blocks={[block('function')]} tree={tree({ counts: new Map([['function', 3]]), onOpen: () => {} }, false)} />)
+    expect(container.querySelector('[aria-label="块操作"]')).toBeNull()
+    expect(container.querySelector('[data-call-tree="function"]')).toBeNull()
+  })
+
+  it('弹框打开时原来的卡片还在，关掉之后弹框没了，焦点回到那个按钮', async () => {
+    const card = block('function', 'mask')
+    function Page(): ReactElement {
+      const [open, setOpen] = useState(false)
+      return (
+        <>
+          <BlockLevel
+            blocks={[card]}
+            tree={tree({ counts: new Map([['mask', 3]]), openAnchor: open ? 'mask' : undefined, onOpen: () => setOpen(true) })}
+          />
+          {open && (
+            <CallTreeDialog
+              kind="function"
+              name="mask_phone"
+              where="utils/phone.py:28"
+              status="ready"
+              trees={[ONE]}
+              onClose={() => setOpen(false)}
+            />
+          )}
+        </>
+      )
+    }
+    await render(<Page />)
+    const button = container.querySelector<HTMLButtonElement>('[data-call-tree="mask"]')!
+    await act(async () => button.click())
+    expect(container.querySelector('[data-id="mask"]')).not.toBeNull()
+    const dialog = document.body.querySelector('[role="dialog"]')
+    expect(dialog).not.toBeNull()
+    expect(dialog!.textContent).toContain('调用树')
+    expect(dialog!.textContent).toContain('mask_phone')
+    expect(dialog!.textContent).toContain('utils/phone.py:28')
+    expect(dialog!.textContent).not.toContain('读取用户资料')
+    expect(dialog!.querySelector('[role="tablist"]')).toBeNull()
+
+    await act(async () => dialog!.querySelector<HTMLButtonElement>('[aria-label="关闭"]')!.click())
+    expect(document.body.querySelector('[role="dialog"]')).toBeNull()
+    expect(container.querySelector('[data-id="mask"]')).not.toBeNull()
+    expect(document.activeElement).toBe(container.querySelector('[data-call-tree="mask"]'))
+  })
+
+  it('点遮罩或按 Esc 关掉弹框', async () => {
+    function Page(): ReactElement {
+      const [open, setOpen] = useState(true)
+      return open
+        ? (
+            <>
+              <div data-id="mask">卡片</div>
+              <CallTreeDialog kind="function" name="mask_phone" where="utils/phone.py:28" status="ready" trees={[ONE]} onClose={() => setOpen(false)} />
+            </>
+          )
+        : <div data-id="mask">卡片</div>
+    }
+    await render(<Page key="overlay" />)
+    const overlay = document.body.querySelector<HTMLElement>('.cr-call-overlay')!
+    await act(async () => overlay.dispatchEvent(new MouseEvent('click', { bubbles: true })))
+    expect(document.body.querySelector('[role="dialog"]')).toBeNull()
+
+    await render(<Page key="esc" />)
+    await act(async () => document.body.querySelector('.cr-call-dialog')!.dispatchEvent(new MouseEvent('click', { bubbles: true })))
+    expect(document.body.querySelector('[role="dialog"]')).not.toBeNull()
+    await act(async () => window.dispatchEvent(new KeyboardEvent('keydown', { key: 'Escape' })))
+    expect(document.body.querySelector('[role="dialog"]')).toBeNull()
+    expect(document.body.textContent).toContain('卡片')
+  })
+
+  it('多于一棵树才有入口切换，点一项换成那棵；只有一棵没有这排', async () => {
+    await render(<CallTreeDialog kind="function" name="mask_phone" where="utils/phone.py:28" status="ready" trees={MANY} onClose={() => {}} />)
+    const tabs = [...document.body.querySelectorAll('[role="tab"]')]
+    expect(tabs.map(tab => tab.textContent?.replace(/\s+/g, ''))).toEqual(['读取用户资料2处', '夜间对账1处'])
+    const body = () => document.body.querySelector('.cr-call-body')!.textContent ?? ''
+    expect(body()).toContain('另外 2 处调用')
+    expect(body()).not.toContain('夜间对账')
+    await act(async () => (tabs[1] as HTMLButtonElement).click())
+    expect(body()).toContain('夜间对账')
+    expect(body()).not.toContain('另外 2 处调用')
+  })
+
+  it('正在查、没有调用者，以及类的「新建」节点', async () => {
+    await render(<CallTreeDialog kind="class" name="" where="" status="loading" trees={[]} onClose={() => {}} />)
+    expect(document.body.textContent).toContain('正在查调用关系')
+    await render(<CallTreeDialog kind="class" name="OrderService" where="billing/order.py:14" status="empty" trees={[]} onClose={() => {}} />)
+    expect(document.body.textContent).toContain('没有调用它的地方')
+    const made = node('新建 OrderService', {
+      kind: 'class',
+      detail: '进入这个类',
+      where: 'billing/order.py:40',
+      children: [node('OrderService', { kind: 'class', current: true, where: 'billing/order.py:14' })],
+    })
+    await render(
+      <CallTreeDialog
+        kind="class"
+        name="OrderService"
+        where="billing/order.py:14"
+        status="ready"
+        trees={[{ id: 'post', name: 'POST /orders', hits: 1, root: node('POST /orders', { detail: '入口', kind: 'function', children: [made] }) }]}
+        onClose={() => {}}
+      />,
+    )
+    expect(document.body.textContent).toContain('新建 OrderService')
+    expect(document.body.textContent).toContain('进入这个类')
+    expect(document.body.textContent).toContain('当前')
+    expect(document.body.textContent).not.toContain('方法')
+    expect(document.body.querySelector('[role="tablist"]')).toBeNull()
+  })
+})
diff --git a/vscode/webview-ui/src/codeReader/CallTreeDialog.tsx b/vscode/webview-ui/src/codeReader/CallTreeDialog.tsx
new file mode 100644
index 0000000..0f97e77
--- /dev/null
+++ b/vscode/webview-ui/src/codeReader/CallTreeDialog.tsx
@@ -0,0 +1,120 @@
+/**
+ * 调用树弹框：盖在编辑区上，预览的卡片留在后面。点遮罩、点叉、按 Esc 关掉，焦点回到打开它的按钮。
+ */
+
+import type { ReactElement } from 'react'
+import type { CallTree, CallTreeNode } from './types'
+import { Box, Braces, X } from 'lucide-react'
+import { useEffect, useState } from 'react'
+import { createPortal } from 'react-dom'
+
+export function CallTreeDialog({ kind, name, where, status, trees, onClose }: {
+  /** 当前块的种类，整条路径用这个种类色 */
+  kind: string
+  name: string
+  where: string
+  status: 'loading' | 'empty' | 'ready'
+  trees: readonly CallTree[]
+  onClose: () => void
+}): ReactElement {
+  const [selected, setSelected] = useState(0)
+  const tree = trees[Math.min(selected, Math.max(trees.length - 1, 0))]
+
+  useEffect(() => {
+    const onKey = (event: KeyboardEvent) => {
+      if (event.key !== 'Escape')
+        return
+      document.querySelector<HTMLButtonElement>('[data-call-tree][data-active]')?.focus()
+      onClose()
+    }
+    window.addEventListener('keydown', onKey)
+    return () => window.removeEventListener('keydown', onKey)
+  }, [onClose])
+
+  function close(): void {
+    document.querySelector<HTMLButtonElement>('[data-call-tree][data-active]')?.focus()
+    onClose()
+  }
+
+  return createPortal(
+    <div
+      className="cr-call-overlay"
+      onClick={(event) => {
+        if (event.target === event.currentTarget)
+          close()
+      }}
+    >
+      <div
+        role="dialog"
+        aria-modal="true"
+        aria-label={name ? `调用树 ${name}` : '调用树'}
+        className="cr-call-dialog"
+        data-kind={kind}
+      >
+        <div className="cr-call-title">
+          <span className="cr-call-heading">调用树</span>
+          {name && <span className="cr-call-symbol">{name}</span>}
+          {where && <span className="cr-call-loc">{where}</span>}
+          <button type="button" className="cr-tool cr-call-close" aria-label="关闭" onClick={close}>
+            <X size={16} strokeWidth={1.8} />
+          </button>
+        </div>
+        {status === 'ready' && trees.length > 1 && (
+          <div className="cr-call-entries" role="tablist" aria-label="调用树入口">
+            {trees.map((item, index) => (
+              <button
+                key={item.id}
+                type="button"
+                role="tab"
+                aria-selected={index === selected}
+                data-active={index === selected ? '' : undefined}
+                className="cr-call-entry"
+                onClick={() => setSelected(index)}
+              >
+                <span>{item.name}</span>
+                <span className="cr-call-hits">{`${item.hits} 处`}</span>
+              </button>
+            ))}
+          </div>
+        )}
+        <div className="cr-call-body">
+          {status === 'loading' && <p className="cr-call-note">正在查调用关系</p>}
+          {status === 'empty' && <p className="cr-call-note">没有调用它的地方</p>}
+          {status === 'ready' && tree && <CallNodes node={tree.root} depth={0} path={tree.id} />}
+        </div>
+      </div>
+    </div>,
+    document.body,
+  )
+}
+
+function CallNodes({ node, depth, path }: { node: CallTreeNode, depth: number, path: string }): ReactElement {
+  const Icon = node.kind === 'class' ? Box : Braces
+  return (
+    <>
+      <div className="cr-call-row" style={{ paddingLeft: depth * 22 }}>
+        <span className="cr-call-guide" />
+        <div className="cr-call-card" data-current={node.current ? '' : undefined}>
+          <div className="cr-call-line">
+            <Icon size={14} strokeWidth={1.8} aria-hidden />
+            <span className="cr-call-name">{node.name}</span>
+            {node.current && <span className="cr-call-pill">当前</span>}
+          </div>
+          <div className="cr-call-sub">
+            {node.detail && <span>{node.detail}</span>}
+            <span className="cr-call-loc">{node.where}</span>
+          </div>
+        </div>
+      </div>
+      {node.children.map((child, index) => (
+        <CallNodes key={`${path}/${index}`} node={child} depth={depth + 1} path={`${path}/${index}`} />
+      ))}
+      {node.otherCalls !== undefined && node.otherCalls > 0 && (
+        <div className="cr-call-row" style={{ paddingLeft: (depth + 1) * 22 }}>
+          <span className="cr-call-guide" data-folded="" />
+          <span className="cr-call-folded">{`另外 ${node.otherCalls} 处调用`}</span>
+        </div>
+      )}
+    </>
+  )
+}
diff --git a/vscode/webview-ui/src/codeReader/codeReader.css b/vscode/webview-ui/src/codeReader/codeReader.css
index d2a6914..a6a2bc4 100644
--- a/vscode/webview-ui/src/codeReader/codeReader.css
+++ b/vscode/webview-ui/src/codeReader/codeReader.css
@@ -1281,3 +1281,179 @@ del.cr-diff-word {
   white-space: pre;
   text-overflow: ellipsis;
 }
+
+/* 调用树：盖住编辑区（文件树在预览外面，不会被压暗）。路径用当前块的种类色 */
+.cr-call-count {
+  min-width: 14px;
+  height: 14px;
+  padding: 0 3px;
+  border-radius: 7px;
+  background: var(--vscode-badge-background);
+  color: var(--vscode-badge-foreground);
+  font-size: 9px;
+  font-weight: 700;
+  line-height: 14px;
+  text-align: center;
+}
+.cr-call-overlay {
+  position: fixed;
+  inset: 0;
+  z-index: 40;
+  display: flex;
+  align-items: flex-start;
+  justify-content: center;
+  padding: 32px 24px;
+  background: rgb(0 0 0 / 55%);
+}
+.cr-call-dialog {
+  display: flex;
+  flex-direction: column;
+  width: min(640px, 100%);
+  max-height: 100%;
+  overflow: hidden;
+  border: 1px solid var(--vscode-editorWidget-border, var(--vscode-widget-border, transparent));
+  border-radius: 8px;
+  background: var(--vscode-editorWidget-background, var(--vscode-editor-background));
+  color: var(--vscode-editorWidget-foreground, var(--vscode-foreground));
+  box-shadow: 0 8px 28px var(--vscode-widget-shadow);
+}
+.cr-call-title {
+  display: flex;
+  flex-shrink: 0;
+  align-items: center;
+  gap: 8px;
+  height: 44px;
+  padding: 0 14px;
+  border-bottom: 1px solid var(--vscode-widget-border, var(--vscode-panel-border, transparent));
+}
+.cr-call-heading {
+  font-weight: 600;
+}
+.cr-call-symbol,
+.cr-call-name {
+  color: var(--kind);
+  font-family: var(--vscode-editor-font-family, monospace);
+  font-weight: 600;
+}
+.cr-call-loc {
+  color: var(--vscode-disabledForeground, var(--vscode-descriptionForeground));
+  font-family: var(--vscode-editor-font-family, monospace);
+  font-size: 11px;
+}
+.cr-call-close {
+  display: flex;
+  align-items: center;
+  justify-content: center;
+  width: 24px;
+  height: 24px;
+  margin-left: auto;
+  border: 0;
+  border-radius: 4px;
+  background: transparent;
+  color: var(--vscode-descriptionForeground);
+}
+.cr-call-entries {
+  display: flex;
+  flex-shrink: 0;
+  flex-wrap: wrap;
+  gap: 8px;
+  padding: 12px 16px 4px;
+}
+.cr-call-entry {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  height: 28px;
+  padding: 0 10px;
+  border: 1px solid var(--vscode-widget-border, var(--vscode-panel-border, transparent));
+  border-radius: 6px;
+  background: var(--vscode-input-background, transparent);
+  color: var(--vscode-foreground);
+  font-size: 12px;
+}
+.cr-call-entry[aria-selected="true"] {
+  border-color: var(--vscode-focusBorder);
+  background: var(--vscode-list-activeSelectionBackground);
+  color: var(--vscode-list-activeSelectionForeground);
+  font-weight: 600;
+}
+.cr-call-hits {
+  color: var(--vscode-disabledForeground, var(--vscode-descriptionForeground));
+  font-size: 11px;
+  font-weight: 400;
+}
+.cr-call-entry[aria-selected="true"] .cr-call-hits {
+  color: var(--vscode-list-activeSelectionForeground);
+}
+.cr-call-body {
+  min-height: 0;
+  padding: 12px 16px 16px;
+  overflow: auto;
+}
+.cr-call-note {
+  margin: 8px 0;
+  color: var(--vscode-descriptionForeground);
+}
+.cr-call-row {
+  display: flex;
+  align-items: stretch;
+  gap: 8px;
+}
+.cr-call-row + .cr-call-row {
+  margin-top: 8px;
+}
+.cr-call-guide {
+  flex-shrink: 0;
+  width: 2px;
+  border-radius: 1px;
+  background: var(--kind);
+}
+.cr-call-guide[data-folded] {
+  align-self: center;
+  height: 16px;
+  background: var(--vscode-editorIndentGuide-background1, var(--vscode-tree-inactiveIndentGuidesStroke));
+}
+.cr-call-card {
+  flex: 1;
+  min-width: 0;
+  padding: 7px 10px;
+  border: 1px solid color-mix(in srgb, var(--kind) 35%, transparent);
+  border-radius: 8px;
+  background: color-mix(in srgb, var(--kind) 7%, transparent);
+}
+.cr-call-card[data-current] {
+  border-color: var(--kind);
+  background: color-mix(in srgb, var(--kind) 14%, transparent);
+}
+.cr-call-line,
+.cr-call-sub {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+.cr-call-line {
+  color: var(--kind);
+}
+.cr-call-sub {
+  margin-top: 2px;
+  color: var(--vscode-descriptionForeground);
+  font-size: 12px;
+}
+.cr-call-pill {
+  display: flex;
+  flex-shrink: 0;
+  align-items: center;
+  height: 18px;
+  margin-left: auto;
+  padding: 0 6px;
+  border-radius: 9px;
+  background: var(--kind);
+  color: var(--vscode-editor-background);
+  font-size: 11px;
+  font-weight: 600;
+}
+.cr-call-folded {
+  align-self: center;
+  color: var(--vscode-disabledForeground, var(--vscode-descriptionForeground));
+  font-size: 12px;
+}
diff --git a/vscode/webview-ui/src/codeReader/types.ts b/vscode/webview-ui/src/codeReader/types.ts
index 8d256ef..d2fae7e 100644
--- a/vscode/webview-ui/src/codeReader/types.ts
+++ b/vscode/webview-ui/src/codeReader/types.ts
@@ -445,7 +445,30 @@ export interface StickyScrollSettings {
  * repoLinkBroken：这个仓库链接打不开。没有 symbol 是文件或目录没有；有 symbol 是文件在、这个符号没有；没有 path 是不带路径的引用找不到
  * repoLinkOpened：这个仓库链接打开了。路径在；带了 symbol 时这个符号也在；没有 path 是不带路径的引用找到了
  * repoImagesChecked：id 那次 checkRepoImages 的回答。src 是预览里能直接用的图片地址；没有 src 是文件不在
+ * callTreeCounts：version 这份文档里，每个函数、类落在几棵调用树里（只包括大于 0 的）。不是页面上这个版本的不理
+ * callTree：anchor 那块的调用树。trees 空着是没有调用它的地方。不是页面上这个版本的不理
  */
+export interface CallTreeNode {
+  name: string
+  kind: string
+  /** 第二行。根是「入口」，新建类是「进入这个类」 */
+  detail?: string
+  /** 文件:行，行从 1 起 */
+  where: string
+  current: boolean
+  children: CallTreeNode[]
+  /** 不在通向当前块的路径上的调用次数 */
+  otherCalls?: number
+}
+
+/** 一棵调用树。hits 是这一棵里当前块出现几次。 */
+export interface CallTree {
+  id: string
+  name: string
+  hits: number
+  root: CallTreeNode
+}
+
 export type ExtensionToWebview
   = | DocumentMessage
     | ({ type: 'reveal' } & Reveal)
@@ -469,6 +492,8 @@ export type ExtensionToWebview
     | { type: 'repoLinkOpened', path?: string, symbol?: string }
     | { type: 'repoImagesChecked', id: number, images: { path: string, src?: string }[] }
     | { type: 'focusPathAsk' }
+    | { type: 'callTreeCounts', version: number, counts: Record<string, number> }
+    | { type: 'callTree', version: number, anchor: string, name: string, where: string, trees: CallTree[] }
 
 /**
  * edit：把 startLine..endLine 这几行整行替换成 text（扩展端给每行补回原来第一行的缩进）
@@ -493,6 +518,7 @@ export type ExtensionToWebview
  *   没有 path 是不带路径的引用（`[Name]`、`[Class.member]`），扩展端按这份文件找 symbol
  * checkRepoLinks：预览里这批仓库路径问哪些文件或目录没有，这批不带路径的引用（symbols）问哪些找不到。id 标出是哪一次问
  * checkRepoImages：预览里这批仓库图片，问哪些文件在，在的要预览里能直接用的地址。id 标出是哪一次问
+ * openCallTree：打开 anchor 那块的调用树。version 是这块所在的文档版本
  */
 export type WebviewToExtension
   = | { type: 'ready' }
@@ -516,3 +542,4 @@ export type WebviewToExtension
     | { type: 'openRepoLink', path?: string, symbol?: string }
     | { type: 'checkRepoLinks', id: number, paths: string[], symbols: string[] }
     | { type: 'checkRepoImages', id: number, paths: string[] }
+    | { type: 'openCallTree', version: number, anchor: string }