diff --git a/packages/agent/src/adapters/claude/hooks.test.ts b/packages/agent/src/adapters/claude/hooks.test.ts
index ec096d79d..771aa4399 100644
--- a/packages/agent/src/adapters/claude/hooks.test.ts
+++ b/packages/agent/src/adapters/claude/hooks.test.ts
@@ -7,7 +7,16 @@ vi.mock("../../enrichment/file-enricher", () => ({
   enrichFileForAgent: enrichFileMock,
 }));
 
-import { createReadEnrichmentHook, type EnrichedReadCache } from "./hooks";
+import { Logger } from "../../utils/logger";
+import {
+  createPreToolUseHook,
+  createReadEnrichmentHook,
+  type EnrichedReadCache,
+} from "./hooks";
+import type {
+  PermissionCheckResult,
+  SettingsManager,
+} from "./session/settings";
 
 const stubDeps = {} as FileEnrichmentDeps;
 
@@ -187,3 +196,118 @@ describe("createReadEnrichmentHook", () => {
     expect(content).toBe("foo");
   });
 });
+
+function buildPreToolUseHookInput(
+  toolName: string,
+  toolInput: Record<string, unknown>,
+): HookInput {
+  return {
+    session_id: "test-session",
+    transcript_path: "/tmp/transcript",
+    cwd: "/tmp",
+    hook_event_name: "PreToolUse",
+    tool_name: toolName,
+    tool_use_id: "toolu_1",
+    tool_input: toolInput,
+  } as HookInput;
+}
+
+function buildSettingsManagerStub(
+  result: PermissionCheckResult,
+): SettingsManager {
+  return {
+    checkPermission: () => result,
+  } as unknown as SettingsManager;
+}
+
+describe("createPreToolUseHook", () => {
+  const logger = new Logger({ debug: false });
+
+  test("defers destructive PostHog exec sub-tool to canUseTool via ask", async () => {
+    const settingsManager = buildSettingsManagerStub({
+      decision: "allow",
+      rule: "mcp__posthog__exec",
+      source: "allow",
+    });
+    const hook = createPreToolUseHook(settingsManager, logger);
+    const result = await hook(
+      buildPreToolUseHookInput("mcp__posthog__exec", {
+        command: 'call dashboard-update {"id": 1, "name": "x"}',
+      }),
+      undefined,
+      { signal: new AbortController().signal },
+    );
+
+    expect(result).toMatchObject({
+      continue: true,
+      hookSpecificOutput: {
+        hookEventName: "PreToolUse",
+        permissionDecision: "ask",
+      },
+    });
+  });
+
+  test("allows non-destructive PostHog exec sub-tool via settings rule", async () => {
+    const settingsManager = buildSettingsManagerStub({
+      decision: "allow",
+      rule: "mcp__posthog__exec",
+      source: "allow",
+    });
+    const hook = createPreToolUseHook(settingsManager, logger);
+    const result = await hook(
+      buildPreToolUseHookInput("mcp__posthog__exec", {
+        command: 'call experiment-get {"id": 1}',
+      }),
+      undefined,
+      { signal: new AbortController().signal },
+    );
+
+    expect(result).toEqual({
+      continue: true,
+      hookSpecificOutput: {
+        hookEventName: "PreToolUse",
+        permissionDecision: "allow",
+        permissionDecisionReason:
+          "Allowed by settings rule: mcp__posthog__exec",
+      },
+    });
+  });
+
+  test("allows non-PostHog tool via settings rule unchanged", async () => {
+    const settingsManager = buildSettingsManagerStub({
+      decision: "allow",
+      rule: "Bash(ls:*)",
+      source: "allow",
+    });
+    const hook = createPreToolUseHook(settingsManager, logger);
+    const result = await hook(
+      buildPreToolUseHookInput("Bash", { command: "ls -la" }),
+      undefined,
+      { signal: new AbortController().signal },
+    );
+
+    expect(result).toMatchObject({
+      hookSpecificOutput: { permissionDecision: "allow" },
+    });
+  });
+
+  test("defers when destructive rule is partial-update", async () => {
+    const settingsManager = buildSettingsManagerStub({
+      decision: "allow",
+      rule: "mcp__posthog__exec",
+      source: "allow",
+    });
+    const hook = createPreToolUseHook(settingsManager, logger);
+    const result = await hook(
+      buildPreToolUseHookInput("mcp__posthog__exec", {
+        command: 'call cohorts-partial-update {"id": 1}',
+      }),
+      undefined,
+      { signal: new AbortController().signal },
+    );
+
+    expect(result).toMatchObject({
+      hookSpecificOutput: { permissionDecision: "ask" },
+    });
+  });
+});
diff --git a/packages/agent/src/adapters/claude/hooks.ts b/packages/agent/src/adapters/claude/hooks.ts
index a9a3073f1..3dc59be89 100644
--- a/packages/agent/src/adapters/claude/hooks.ts
+++ b/packages/agent/src/adapters/claude/hooks.ts
@@ -5,6 +5,11 @@ import {
 } from "../../enrichment/file-enricher";
 import type { Logger } from "../../utils/logger";
 import { stripCatLineNumbers } from "./conversion/sdk-to-acp";
+import {
+  extractPostHogSubTool,
+  isPostHogDestructiveSubTool,
+  isPostHogExecTool,
+} from "./permissions/posthog-exec-gate";
 import type { SettingsManager } from "./session/settings";
 import type { CodeExecutionMode } from "./tools";
 
@@ -237,6 +242,25 @@ export const createPreToolUseHook =
       );
     }
 
+    // Defer destructive PostHog exec sub-tools to canUseTool so the
+    // sub-tool gate can re-prompt. Returning `{ continue: true }` is
+    // not enough — the SDK then falls back to its default permission
+    // flow which re-checks the same allow rule. We must force "ask"
+    // so the SDK invokes canUseTool.
+    if (permissionCheck.decision === "allow" && isPostHogExecTool(toolName)) {
+      const subTool = extractPostHogSubTool(toolInput);
+      if (subTool && isPostHogDestructiveSubTool(subTool)) {
+        return {
+          continue: true,
+          hookSpecificOutput: {
+            hookEventName: "PreToolUse" as const,
+            permissionDecision: "ask" as const,
+            permissionDecisionReason: `Destructive PostHog sub-tool '${subTool}' requires explicit approval`,
+          },
+        };
+      }
+    }
+
     switch (permissionCheck.decision) {
       case "allow":
         return {
diff --git a/packages/agent/src/adapters/claude/permissions/permission-handlers.test.ts b/packages/agent/src/adapters/claude/permissions/permission-handlers.test.ts
index 6b7139367..5d138c2f1 100644
--- a/packages/agent/src/adapters/claude/permissions/permission-handlers.test.ts
+++ b/packages/agent/src/adapters/claude/permissions/permission-handlers.test.ts
@@ -143,6 +143,158 @@ describe("canUseTool MCP approval enforcement", () => {
     expect(result.behavior).toBe("allow");
   });
 
+  it("bypasses the PostHog exec gate in auto mode", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+    const hasApproval = vi.fn().mockReturnValue(false);
+    const addApproval = vi.fn().mockResolvedValue(undefined);
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call experiment-update {}" },
+      session: {
+        permissionMode: "auto",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: hasApproval,
+          addPostHogExecApproval: addApproval,
+        },
+      },
+    });
+    const result = await canUseTool(context);
+
+    expect(result.behavior).toBe("allow");
+    expect(context.client.requestPermission).not.toHaveBeenCalled();
+    expect(hasApproval).not.toHaveBeenCalled();
+    expect(addApproval).not.toHaveBeenCalled();
+  });
+
+  it("bypasses the PostHog exec gate in bypassPermissions mode", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call feature-flag-delete {}" },
+      session: {
+        permissionMode: "bypassPermissions",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: vi.fn().mockReturnValue(false),
+          addPostHogExecApproval: vi.fn(),
+        },
+      },
+    });
+    const result = await canUseTool(context);
+
+    expect(result.behavior).toBe("allow");
+    expect(context.client.requestPermission).not.toHaveBeenCalled();
+  });
+
+  it("short-circuits when a PostHog exec sub-tool was previously approved", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call experiment-update {}" },
+      session: {
+        permissionMode: "default",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: vi
+            .fn()
+            .mockImplementation((s: string) => s === "experiment-update"),
+          addPostHogExecApproval: vi.fn(),
+        },
+      },
+    });
+    const result = await canUseTool(context);
+
+    expect(result.behavior).toBe("allow");
+    expect(context.client.requestPermission).not.toHaveBeenCalled();
+  });
+
+  it("prompts for an unapproved destructive PostHog sub-tool and persists on allow_always", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+    const addApproval = vi.fn().mockResolvedValue(undefined);
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call notebooks-destroy {}" },
+      session: {
+        permissionMode: "default",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: vi.fn().mockReturnValue(false),
+          addPostHogExecApproval: addApproval,
+        },
+      },
+      client: {
+        sessionUpdate: vi.fn().mockResolvedValue(undefined),
+        requestPermission: vi.fn().mockResolvedValue({
+          outcome: { outcome: "selected", optionId: "allow_always" },
+        }),
+      },
+    });
+    const result = await canUseTool(context);
+
+    expect(result.behavior).toBe("allow");
+    expect(context.client.requestPermission).toHaveBeenCalledWith(
+      expect.objectContaining({
+        toolCall: expect.objectContaining({
+          title: "The agent wants to run `notebooks-destroy` on PostHog",
+        }),
+      }),
+    );
+    expect(addApproval).toHaveBeenCalledWith("notebooks-destroy");
+  });
+
+  it("prompts but does not persist on allow_once", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+    const addApproval = vi.fn();
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call experiment-delete {}" },
+      session: {
+        permissionMode: "default",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: vi.fn().mockReturnValue(false),
+          addPostHogExecApproval: addApproval,
+        },
+      },
+      client: {
+        sessionUpdate: vi.fn().mockResolvedValue(undefined),
+        requestPermission: vi.fn().mockResolvedValue({
+          outcome: { outcome: "selected", optionId: "allow" },
+        }),
+      },
+    });
+    const result = await canUseTool(context);
+
+    expect(result.behavior).toBe("allow");
+    expect(addApproval).not.toHaveBeenCalled();
+  });
+
+  it("does not gate non-destructive PostHog sub-tools", async () => {
+    setMcpToolApprovalStates({ mcp__posthog__exec: "approved" });
+    const addApproval = vi.fn();
+
+    const context = createContext("mcp__posthog__exec", {
+      toolInput: { command: "call experiment-get-all {}" },
+      session: {
+        permissionMode: "default",
+        settingsManager: {
+          getRepoRoot: vi.fn().mockReturnValue("/repo"),
+          hasPostHogExecApproval: vi.fn().mockReturnValue(false),
+          addPostHogExecApproval: addApproval,
+        },
+      },
+    });
+    const result = await canUseTool(context);
+
+    // Non-destructive sub-tool falls through the gate. With approved MCP state
+    // and non-read-only tool metadata, it hits the default permission flow,
+    // which auto-allows via our mocked requestPermission. The gate must not
+    // have prompted with a PostHog-specific title, and must not have persisted.
+    expect(result.behavior).toBe("allow");
+    expect(addApproval).not.toHaveBeenCalled();
+  });
+
   it("emits tool denial notification for do_not_use", async () => {
     setMcpToolApprovalStates({
       mcp__server__denied_tool: "do_not_use",
diff --git a/packages/agent/src/adapters/claude/permissions/permission-handlers.ts b/packages/agent/src/adapters/claude/permissions/permission-handlers.ts
index f9e6293c7..f8bb8d5d5 100644
--- a/packages/agent/src/adapters/claude/permissions/permission-handlers.ts
+++ b/packages/agent/src/adapters/claude/permissions/permission-handlers.ts
@@ -31,6 +31,11 @@ import {
   buildExitPlanModePermissionOptions,
   buildPermissionOptions,
 } from "./permission-options";
+import {
+  extractPostHogSubTool,
+  isPostHogDestructiveSubTool,
+  isPostHogExecTool,
+} from "./posthog-exec-gate";
 
 export type ToolPermissionResult =
   | {
@@ -78,6 +83,18 @@ async function emitToolDenial(
   });
 }
 
+async function buildDenialResult(
+  context: ToolHandlerContext,
+  response: RequestPermissionResponse,
+): Promise<ToolPermissionResult> {
+  const feedback = (response._meta?.customInput as string | undefined)?.trim();
+  const message = feedback
+    ? `User refused permission to run tool with feedback: ${feedback}`
+    : "User refused permission to run tool";
+  await emitToolDenial(context, message);
+  return { behavior: "deny", message, interrupt: !feedback };
+}
+
 function getPlanFromFile(
   session: Session,
   fileContentCache: { [key: string]: string },
@@ -389,16 +406,9 @@ async function handleDefaultPermissionFlow(
       behavior: "allow",
       updatedInput: toolInput as Record<string, unknown>,
     };
-  } else {
-    const feedback = (
-      response._meta?.customInput as string | undefined
-    )?.trim();
-    const message = feedback
-      ? `User refused permission to run tool with feedback: ${feedback}`
-      : "User refused permission to run tool";
-    await emitToolDenial(context, message);
-    return { behavior: "deny", message, interrupt: !feedback };
   }
+
+  return buildDenialResult(context, response);
 }
 
 function parseMcpToolName(toolName: string): {
@@ -479,12 +489,74 @@ async function handleMcpApprovalFlow(
     };
   }
 
-  const feedback = (response._meta?.customInput as string | undefined)?.trim();
-  const message = feedback
-    ? `User refused permission to run tool with feedback: ${feedback}`
-    : "User refused permission to run tool";
-  await emitToolDenial(context, message);
-  return { behavior: "deny", message, interrupt: !feedback };
+  return buildDenialResult(context, response);
+}
+
+async function handlePostHogExecApprovalFlow(
+  context: ToolHandlerContext,
+  subTool: string,
+): Promise<ToolPermissionResult> {
+  const { toolName, toolInput, toolUseID, client, sessionId, session } =
+    context;
+
+  const response = await client.requestPermission({
+    options: [
+      { kind: "allow_once", name: "Yes", optionId: "allow" },
+      {
+        kind: "allow_always",
+        name: "Yes, always allow",
+        optionId: "allow_always",
+      },
+      {
+        kind: "reject_once",
+        name: "Type here to tell the agent what to do differently",
+        optionId: "reject",
+        _meta: { customInput: true },
+      },
+    ],
+    sessionId,
+    toolCall: {
+      toolCallId: toolUseID,
+      title: `The agent wants to run \`${subTool}\` on PostHog`,
+      kind: "other",
+      content: [
+        {
+          type: "content" as const,
+          content: text(
+            "This will modify live PostHog data. Approve to run this sub-tool.",
+          ),
+        },
+      ],
+      rawInput: { ...(toolInput as Record<string, unknown>), toolName },
+    },
+  });
+
+  if (context.signal?.aborted || response.outcome?.outcome === "cancelled") {
+    throw new Error("Tool use aborted");
+  }
+
+  if (
+    response.outcome?.outcome === "selected" &&
+    (response.outcome.optionId === "allow" ||
+      response.outcome.optionId === "allow_always")
+  ) {
+    if (response.outcome.optionId === "allow_always") {
+      try {
+        await session.settingsManager.addPostHogExecApproval(subTool);
+      } catch (error) {
+        context.logger.warn(
+          "[canUseTool] Failed to persist PostHog exec approval",
+          { error: error instanceof Error ? error.message : String(error) },
+        );
+      }
+    }
+    return {
+      behavior: "allow",
+      updatedInput: toolInput as Record<string, unknown>,
+    };
+  }
+
+  return buildDenialResult(context, response);
 }
 
 function handlePlanFileException(
@@ -602,6 +674,28 @@ export async function canUseTool(
     if (approvalState === "needs_approval") {
       return handleMcpApprovalFlow(context);
     }
+
+    if (isPostHogExecTool(toolName)) {
+      const subTool = extractPostHogSubTool(toolInput);
+      if (subTool && isPostHogDestructiveSubTool(subTool)) {
+        if (
+          session.permissionMode === "auto" ||
+          session.permissionMode === "bypassPermissions"
+        ) {
+          return {
+            behavior: "allow",
+            updatedInput: toolInput as Record<string, unknown>,
+          };
+        }
+        if (session.settingsManager.hasPostHogExecApproval(subTool)) {
+          return {
+            behavior: "allow",
+            updatedInput: toolInput as Record<string, unknown>,
+          };
+        }
+        return handlePostHogExecApprovalFlow(context, subTool);
+      }
+    }
   }
 
   if (isToolAllowedForMode(toolName, session.permissionMode)) {
diff --git a/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.test.ts b/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.test.ts
new file mode 100644
index 000000000..6c2e82a93
--- /dev/null
+++ b/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.test.ts
@@ -0,0 +1,84 @@
+import { describe, expect, it } from "vitest";
+import {
+  extractPostHogSubTool,
+  isPostHogDestructiveSubTool,
+  isPostHogExecTool,
+} from "./posthog-exec-gate";
+
+describe("isPostHogExecTool", () => {
+  it("matches the bare posthog exec tool", () => {
+    expect(isPostHogExecTool("mcp__posthog__exec")).toBe(true);
+  });
+
+  it("matches plugin-prefixed variants", () => {
+    expect(isPostHogExecTool("mcp__posthog_posthog__exec")).toBe(true);
+    expect(isPostHogExecTool("mcp__posthog_cloud__exec")).toBe(true);
+  });
+
+  it("rejects other MCP tools", () => {
+    expect(isPostHogExecTool("mcp__posthog__list")).toBe(false);
+    expect(isPostHogExecTool("mcp__other__exec")).toBe(false);
+    expect(isPostHogExecTool("mcp__acp__Bash")).toBe(false);
+    expect(isPostHogExecTool("Bash")).toBe(false);
+  });
+});
+
+describe("extractPostHogSubTool", () => {
+  it("parses a bare `call <tool>` command", () => {
+    expect(extractPostHogSubTool({ command: "call experiment-update" })).toBe(
+      "experiment-update",
+    );
+  });
+
+  it("parses `call --json <tool>`", () => {
+    expect(
+      extractPostHogSubTool({
+        command: 'call --json experiment-update {"id":1}',
+      }),
+    ).toBe("experiment-update");
+  });
+
+  it("tolerates leading whitespace", () => {
+    expect(extractPostHogSubTool({ command: "  call foo-delete" })).toBe(
+      "foo-delete",
+    );
+  });
+
+  it("returns null for non-`call` verbs", () => {
+    expect(extractPostHogSubTool({ command: "tools" })).toBeNull();
+    expect(extractPostHogSubTool({ command: "search experiments" })).toBeNull();
+    expect(extractPostHogSubTool({ command: "info flag-get" })).toBeNull();
+  });
+
+  it("returns null for missing or malformed input", () => {
+    expect(extractPostHogSubTool(undefined)).toBeNull();
+    expect(extractPostHogSubTool(null)).toBeNull();
+    expect(extractPostHogSubTool({})).toBeNull();
+    expect(extractPostHogSubTool({ command: 42 })).toBeNull();
+    expect(extractPostHogSubTool({ command: "" })).toBeNull();
+  });
+});
+
+describe("isPostHogDestructiveSubTool", () => {
+  it("matches update/delete/destroy/partial-update as whole segments", () => {
+    expect(isPostHogDestructiveSubTool("experiment-update")).toBe(true);
+    expect(isPostHogDestructiveSubTool("feature-flag-delete")).toBe(true);
+    expect(isPostHogDestructiveSubTool("notebooks-destroy")).toBe(true);
+    expect(isPostHogDestructiveSubTool("experiment-partial-update")).toBe(true);
+    expect(isPostHogDestructiveSubTool("update-something")).toBe(true);
+    expect(isPostHogDestructiveSubTool("delete")).toBe(true);
+  });
+
+  it("does not match read verbs or unrelated tokens", () => {
+    expect(isPostHogDestructiveSubTool("experiment-get")).toBe(false);
+    expect(isPostHogDestructiveSubTool("feature-flag-list")).toBe(false);
+    expect(isPostHogDestructiveSubTool("experiment-create")).toBe(false);
+    expect(isPostHogDestructiveSubTool("insights-pause")).toBe(false);
+  });
+
+  it("does not match substrings inside other words", () => {
+    // "updated" should not count — must be a whole segment
+    expect(isPostHogDestructiveSubTool("get-updated-events")).toBe(false);
+    expect(isPostHogDestructiveSubTool("deleter-test")).toBe(false);
+  });
+});
diff --git a/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.ts b/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.ts
new file mode 100644
index 000000000..2ecdb8c6e
--- /dev/null
+++ b/packages/agent/src/adapters/claude/permissions/posthog-exec-gate.ts
@@ -0,0 +1,30 @@
+/**
+ * The PostHog MCP exposes a single `exec` dispatcher tool that runs
+ * subcommands like `call [--json] <tool-name> [json]`. Once the user approves
+ * `mcp__posthog__exec` once, every subsequent call goes through silently —
+ * including destructive ones. These helpers let `canUseTool` re-gate the
+ * destructive subset (update/delete family) at sub-tool granularity.
+ */
+
+const POSTHOG_EXEC_TOOL_RE = /^mcp__posthog(?:_[^_]+)*__exec$/;
+
+const POSTHOG_CALL_COMMAND_RE = /^\s*call\s+(?:--json\s+)?([a-zA-Z0-9_-]+)/;
+
+const POSTHOG_DESTRUCTIVE_SUBTOOL_RE =
+  /(^|-)(partial-update|update|delete|destroy)(-|$)/i;
+
+export function isPostHogExecTool(toolName: string): boolean {
+  return POSTHOG_EXEC_TOOL_RE.test(toolName);
+}
+
+export function extractPostHogSubTool(toolInput: unknown): string | null {
+  if (!toolInput || typeof toolInput !== "object") return null;
+  const command = (toolInput as { command?: unknown }).command;
+  if (typeof command !== "string") return null;
+  const match = command.match(POSTHOG_CALL_COMMAND_RE);
+  return match ? (match[1] ?? null) : null;
+}
+
+export function isPostHogDestructiveSubTool(subTool: string): boolean {
+  return POSTHOG_DESTRUCTIVE_SUBTOOL_RE.test(subTool);
+}
diff --git a/packages/agent/src/adapters/claude/session/settings.test.ts b/packages/agent/src/adapters/claude/session/settings.test.ts
index de31eb3d3..960c5d4f6 100644
--- a/packages/agent/src/adapters/claude/session/settings.test.ts
+++ b/packages/agent/src/adapters/claude/session/settings.test.ts
@@ -127,6 +127,56 @@ describe("SettingsManager per-repo persistence", () => {
     expect(await fs.promises.readFile(filePath, "utf-8")).toBe(original);
   });
 
+  it("persists PostHog exec approvals and sees them across worktrees", async () => {
+    const writer = new SettingsManager(worktree);
+    await writer.initialize();
+    await writer.addPostHogExecApproval("experiment-update");
+
+    const filePath = path.join(mainRepo, ".claude", "settings.local.json");
+    const contents = JSON.parse(await fs.promises.readFile(filePath, "utf-8"));
+    expect(contents.posthogApprovedExecTools).toEqual(["experiment-update"]);
+
+    const sibling = path.join(tmpRoot, "wt-ph");
+    runGit(mainRepo, ["worktree", "add", "-b", "other-ph", sibling]);
+    const reader = new SettingsManager(sibling);
+    await reader.initialize();
+    expect(reader.hasPostHogExecApproval("experiment-update")).toBe(true);
+    expect(reader.hasPostHogExecApproval("experiment-delete")).toBe(false);
+  });
+
+  it("dedupes repeated PostHog exec approvals", async () => {
+    const manager = new SettingsManager(worktree);
+    await manager.initialize();
+
+    await manager.addPostHogExecApproval("foo-update");
+    await manager.addPostHogExecApproval("foo-update");
+    await manager.addPostHogExecApproval("bar-delete");
+
+    const filePath = path.join(mainRepo, ".claude", "settings.local.json");
+    const contents = JSON.parse(await fs.promises.readFile(filePath, "utf-8"));
+    expect(contents.posthogApprovedExecTools).toEqual([
+      "foo-update",
+      "bar-delete",
+    ]);
+  });
+
+  it("concurrent addPostHogExecApproval calls do not clobber each other", async () => {
+    const manager = new SettingsManager(worktree);
+    await manager.initialize();
+
+    await Promise.all([
+      manager.addPostHogExecApproval("a-update"),
+      manager.addPostHogExecApproval("b-delete"),
+      manager.addPostHogExecApproval("c-destroy"),
+    ]);
+
+    const filePath = path.join(mainRepo, ".claude", "settings.local.json");
+    const contents = JSON.parse(await fs.promises.readFile(filePath, "utf-8"));
+    expect(contents.posthogApprovedExecTools).toEqual(
+      expect.arrayContaining(["a-update", "b-delete", "c-destroy"]),
+    );
+  });
+
   it("concurrent addAllowRules calls do not clobber each other", async () => {
     const manager = new SettingsManager(worktree);
     await manager.initialize();
diff --git a/packages/agent/src/adapters/claude/session/settings.ts b/packages/agent/src/adapters/claude/session/settings.ts
index 67ce16670..0a2b8e39b 100644
--- a/packages/agent/src/adapters/claude/session/settings.ts
+++ b/packages/agent/src/adapters/claude/session/settings.ts
@@ -196,6 +196,7 @@ export interface ClaudeCodeSettings {
   permissions?: PermissionSettings;
   env?: Record<string, string>;
   model?: string;
+  posthogApprovedExecTools?: string[];
 }
 
 export type PermissionDecision = "allow" | "deny" | "ask";
@@ -295,6 +296,7 @@ export class SettingsManager {
       ask: [],
     };
     const merged: ClaudeCodeSettings = { permissions };
+    const posthogApprovedExecTools = new Set<string>();
 
     for (const settings of allSettings) {
       if (settings.permissions) {
@@ -323,6 +325,15 @@ export class SettingsManager {
       if (settings.model) {
         merged.model = settings.model;
       }
+      if (settings.posthogApprovedExecTools) {
+        for (const tool of settings.posthogApprovedExecTools) {
+          posthogApprovedExecTools.add(tool);
+        }
+      }
+    }
+
+    if (posthogApprovedExecTools.size > 0) {
+      merged.posthogApprovedExecTools = Array.from(posthogApprovedExecTools);
     }
 
     this.mergedSettings = merged;
@@ -405,6 +416,43 @@ export class SettingsManager {
     }
   }
 
+  hasPostHogExecApproval(subTool: string): boolean {
+    return (
+      this.mergedSettings.posthogApprovedExecTools?.includes(subTool) ?? false
+    );
+  }
+
+  /**
+   * Persists an approved PostHog MCP `exec` sub-tool (e.g. `experiment-update`)
+   * to the local settings file so future calls skip the prompt. Mirrors
+   * `addAllowRules` — serialised via `writeMutex`, atomic temp-file + rename.
+   */
+  async addPostHogExecApproval(subTool: string): Promise<void> {
+    if (!subTool) return;
+    if (!this.initialized) await this.initialize();
+    await this.writeMutex.acquire();
+    try {
+      const filePath = this.getLocalSettingsPath();
+      const existing = await readSettingsFileForUpdate(filePath);
+      const current = new Set(existing.posthogApprovedExecTools ?? []);
+      if (current.has(subTool)) {
+        return;
+      }
+      current.add(subTool);
+      const next: ClaudeCodeSettings = {
+        ...existing,
+        posthogApprovedExecTools: Array.from(current),
+      };
+      await fs.promises.mkdir(path.dirname(filePath), { recursive: true });
+      await writeFileAtomic(filePath, `${JSON.stringify(next, null, 2)}\n`);
+
+      this.localSettings = next;
+      this.mergeAllSettings();
+    } finally {
+      this.writeMutex.release();
+    }
+  }
+
   async setCwd(cwd: string): Promise<void> {
     if (this.cwd === cwd) return;
     if (this.initPromise) await this.initPromise;