diff --git a/CHANGELOG.md b/CHANGELOG.md
index 36625a134e1..66cdaf15bb6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -17,6 +17,7 @@ Docs: https://docs.openclaw.ai
 - Memory/sqlite-vec: emit the degraded sqlite-vec warning once per degraded episode instead of repeating it for every file write, while preserving the latch across safe-reindex rollback and resetting it when vector state is genuinely rebuilt. (#67898) Thanks @rubencu.
 - Reply/block streaming: preserve post-stream incomplete-turn error payloads after block streaming already emitted content, so users get the warning instead of silence. (#67991) Thanks @obviyus.
 - Telegram/streaming: clear the compaction replay guard after visible non-final boundaries so a post-tool assistant reply rotates to a fresh preview instead of editing the pre-compaction message. (#67993) Thanks @obviyus.
+- Matrix: fix `sessions_spawn --thread` subagent session spawning — thread binding creation, cleanup on session end, and completion-message delivery target resolution now work end-to-end. (#67643) Thanks @eejohnso-ops.
 
 ## 2026.4.15
 
diff --git a/extensions/matrix/index.ts b/extensions/matrix/index.ts
index 9dd62e49be0..e46b307e1b6 100644
--- a/extensions/matrix/index.ts
+++ b/extensions/matrix/index.ts
@@ -2,6 +2,15 @@ import { defineBundledChannelEntry } from "openclaw/plugin-sdk/channel-entry-con
 import { formatErrorMessage } from "openclaw/plugin-sdk/error-runtime";
 import { registerMatrixCliMetadata } from "./cli-metadata.js";
 
+type MatrixSubagentHooksModule = typeof import("./src/matrix/subagent-hooks.js");
+
+let matrixSubagentHooksPromise: Promise<MatrixSubagentHooksModule> | null = null;
+
+function loadMatrixSubagentHooksModule() {
+  matrixSubagentHooksPromise ??= import("./src/matrix/subagent-hooks.js");
+  return matrixSubagentHooksPromise;
+}
+
 export default defineBundledChannelEntry({
   id: "matrix",
   name: "Matrix",
@@ -47,5 +56,18 @@ export default defineBundledChannelEntry({
       const { handleVerificationStatus } = await import("./plugin-entry.handlers.runtime.js");
       await handleVerificationStatus(ctx);
     });
+
+    api.on("subagent_spawning", async (event) => {
+      const { handleMatrixSubagentSpawning } = await loadMatrixSubagentHooksModule();
+      return await handleMatrixSubagentSpawning(api, event);
+    });
+    api.on("subagent_ended", async (event) => {
+      const { handleMatrixSubagentEnded } = await loadMatrixSubagentHooksModule();
+      await handleMatrixSubagentEnded(event);
+    });
+    api.on("subagent_delivery_target", async (event) => {
+      const { handleMatrixSubagentDeliveryTarget } = await loadMatrixSubagentHooksModule();
+      return handleMatrixSubagentDeliveryTarget(event);
+    });
   },
 });
diff --git a/extensions/matrix/src/matrix/subagent-hooks.test.ts b/extensions/matrix/src/matrix/subagent-hooks.test.ts
new file mode 100644
index 00000000000..41cb50f6030
--- /dev/null
+++ b/extensions/matrix/src/matrix/subagent-hooks.test.ts
@@ -0,0 +1,568 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+// Hoisted stubs referenced in vi.mock factories below
+const bindMock = vi.hoisted(() => vi.fn());
+const getManagerMock = vi.hoisted(() => vi.fn());
+const listAllBindingsMock = vi.hoisted(() => vi.fn((): any[] => []));
+const listBindingsForAccountMock = vi.hoisted(() => vi.fn((): any[] => []));
+const removeBindingRecordMock = vi.hoisted(() => vi.fn(() => false));
+const resolveMatrixBaseConfigMock = vi.hoisted(() => vi.fn((): any => ({})));
+const findMatrixAccountConfigMock = vi.hoisted(() => vi.fn((): any => undefined));
+
+vi.mock("openclaw/plugin-sdk/conversation-binding-runtime", () => ({
+  getSessionBindingService: () => ({ bind: bindMock }),
+}));
+
+vi.mock("./account-config.js", () => ({
+  resolveMatrixBaseConfig: resolveMatrixBaseConfigMock,
+  findMatrixAccountConfig: findMatrixAccountConfigMock,
+}));
+
+vi.mock("./thread-bindings-shared.js", () => ({
+  getMatrixThreadBindingManager: getManagerMock,
+  listAllBindings: listAllBindingsMock,
+  listBindingsForAccount: listBindingsForAccountMock,
+  removeBindingRecord: removeBindingRecordMock,
+}));
+
+import {
+  handleMatrixSubagentDeliveryTarget,
+  handleMatrixSubagentEnded,
+  handleMatrixSubagentSpawning,
+} from "./subagent-hooks.js";
+
+// A minimal fake api — only config is used by these hooks
+const fakeApi = { config: {} } as never;
+
+function makeSpawnEvent(
+  overrides: Partial<{
+    threadRequested: boolean;
+    channel: string;
+    accountId: string;
+    to: string;
+    childSessionKey: string;
+    agentId: string;
+    label: string;
+  }> = {},
+) {
+  return {
+    threadRequested: overrides.threadRequested ?? true,
+    requester: {
+      channel: overrides.channel ?? "matrix",
+      accountId: overrides.accountId ?? "default",
+      to: overrides.to ?? "room:!room123:example.org",
+    },
+    childSessionKey: overrides.childSessionKey ?? "agent:default:subagent:child",
+    agentId: overrides.agentId ?? "worker",
+    label: overrides.label,
+  };
+}
+
+describe("handleMatrixSubagentSpawning", () => {
+  beforeEach(() => {
+    bindMock.mockReset();
+    getManagerMock.mockReset();
+    resolveMatrixBaseConfigMock.mockReset();
+    findMatrixAccountConfigMock.mockReset();
+    // Default: bindings enabled, spawn enabled
+    resolveMatrixBaseConfigMock.mockReturnValue({
+      threadBindings: { enabled: true, spawnSubagentSessions: true },
+    });
+    findMatrixAccountConfigMock.mockReturnValue(undefined);
+    // Default: manager exists
+    getManagerMock.mockReturnValue({ persist: vi.fn() });
+    // Default: bind resolves ok
+    bindMock.mockResolvedValue({ conversation: {} });
+  });
+
+  it("returns undefined when threadRequested is false", async () => {
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({ threadRequested: false }),
+    );
+    expect(result).toBeUndefined();
+    expect(bindMock).not.toHaveBeenCalled();
+  });
+
+  it("returns undefined when channel is not matrix", async () => {
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({ channel: "slack" }),
+    );
+    expect(result).toBeUndefined();
+    expect(bindMock).not.toHaveBeenCalled();
+  });
+
+  it("returns undefined when channel has mixed casing but is still matrix", async () => {
+    // channel.trim().toLowerCase() must equal "matrix"
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({ channel: " Matrix " }),
+    );
+    expect(result).not.toBeUndefined();
+    // It proceeds (no early-return for non-matrix)
+  });
+
+  it("returns error when thread bindings are disabled", async () => {
+    resolveMatrixBaseConfigMock.mockReturnValue({
+      threadBindings: { enabled: false, spawnSubagentSessions: true },
+    });
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent());
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("thread bindings are disabled"),
+      }),
+    );
+  });
+
+  it("returns error when spawnSubagentSessions is false", async () => {
+    resolveMatrixBaseConfigMock.mockReturnValue({
+      threadBindings: { enabled: true, spawnSubagentSessions: false },
+    });
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent());
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("spawnSubagentSessions"),
+      }),
+    );
+  });
+
+  it("returns error when spawnSubagentSessions defaults to false (no config)", async () => {
+    resolveMatrixBaseConfigMock.mockReturnValue({});
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent());
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("spawnSubagentSessions"),
+      }),
+    );
+  });
+
+  it("returns error when requester.to has no room target", async () => {
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({ to: "@user:example.org" }),
+    );
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("no room target"),
+      }),
+    );
+  });
+
+  it("returns error when requester.to is empty", async () => {
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent({ to: "" }));
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("no room target"),
+      }),
+    );
+  });
+
+  it("returns error when no binding manager is available for the account", async () => {
+    getManagerMock.mockReturnValue(null);
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent());
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("No Matrix thread binding manager"),
+      }),
+    );
+  });
+
+  it("calls bind with the resolved room id and returns ok", async () => {
+    bindMock.mockResolvedValue({ conversation: {} });
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({
+        accountId: "ops",
+        to: "room:!roomAbc:technerik.com",
+        childSessionKey: "agent:ops:subagent:worker",
+        agentId: "builder",
+        label: "Build Agent",
+      }),
+    );
+
+    expect(bindMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        targetSessionKey: "agent:ops:subagent:worker",
+        targetKind: "subagent",
+        conversation: expect.objectContaining({
+          channel: "matrix",
+          accountId: "ops",
+          conversationId: "!roomAbc:technerik.com",
+        }),
+        placement: "child",
+        metadata: expect.objectContaining({
+          agentId: "builder",
+          label: "Build Agent",
+        }),
+      }),
+    );
+    expect(result).toEqual({ status: "ok", threadBindingReady: true });
+  });
+
+  it("uses 'default' as accountId when requester.accountId is absent", async () => {
+    bindMock.mockResolvedValue({ conversation: {} });
+    await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent({ accountId: undefined as never }));
+    expect(getManagerMock).toHaveBeenCalledWith("default");
+    expect(bindMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        conversation: expect.objectContaining({ accountId: "default" }),
+      }),
+    );
+  });
+
+  it("returns error when bind() throws", async () => {
+    bindMock.mockRejectedValue(new Error("provider auth failed"));
+    const result = await handleMatrixSubagentSpawning(fakeApi, makeSpawnEvent());
+    expect(result).toEqual(
+      expect.objectContaining({
+        status: "error",
+        error: expect.stringContaining("provider auth failed"),
+      }),
+    );
+  });
+
+  it("respects per-account threadBindings override over base config", async () => {
+    // Base says spawnSubagentSessions=false; account override says true
+    resolveMatrixBaseConfigMock.mockReturnValue({
+      threadBindings: { enabled: true, spawnSubagentSessions: false },
+    });
+    findMatrixAccountConfigMock.mockReturnValue({
+      threadBindings: { spawnSubagentSessions: true },
+    });
+    bindMock.mockResolvedValue({ conversation: {} });
+
+    const result = await handleMatrixSubagentSpawning(
+      fakeApi,
+      makeSpawnEvent({ accountId: "forge" }),
+    );
+    expect(result).toEqual({ status: "ok", threadBindingReady: true });
+  });
+});
+
+describe("handleMatrixSubagentEnded", () => {
+  const mockManager = { persist: vi.fn() };
+
+  beforeEach(() => {
+    getManagerMock.mockReset();
+    listAllBindingsMock.mockReset();
+    listBindingsForAccountMock.mockReset();
+    removeBindingRecordMock.mockReset();
+    mockManager.persist.mockReset();
+  });
+
+  it("does nothing when no matching bindings exist", async () => {
+    listBindingsForAccountMock.mockReturnValue([]);
+    await handleMatrixSubagentEnded({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+    });
+    expect(getManagerMock).not.toHaveBeenCalled();
+  });
+
+  it("removes matching bindings and calls persist on the manager", async () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+    removeBindingRecordMock.mockReturnValue(true);
+    getManagerMock.mockReturnValue(mockManager);
+    mockManager.persist.mockResolvedValue(undefined);
+
+    await handleMatrixSubagentEnded({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+    });
+
+    expect(removeBindingRecordMock).toHaveBeenCalledWith(binding);
+    expect(getManagerMock).toHaveBeenCalledWith("ops");
+    expect(mockManager.persist).toHaveBeenCalled();
+  });
+
+  it("skips persist when removeBindingRecord returns false (binding not found in store)", async () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:orphan",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+    removeBindingRecordMock.mockReturnValue(false);
+
+    await handleMatrixSubagentEnded({
+      targetSessionKey: "agent:ops:subagent:orphan",
+      targetKind: "subagent",
+      accountId: "ops",
+    });
+
+    expect(getManagerMock).not.toHaveBeenCalled();
+  });
+
+  it("falls back to listAllBindings when accountId is absent", async () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listAllBindingsMock.mockReturnValue([binding]);
+    removeBindingRecordMock.mockReturnValue(true);
+    getManagerMock.mockReturnValue(mockManager);
+    mockManager.persist.mockResolvedValue(undefined);
+
+    await handleMatrixSubagentEnded({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+    });
+
+    expect(listAllBindingsMock).toHaveBeenCalled();
+    expect(listBindingsForAccountMock).not.toHaveBeenCalled();
+    expect(mockManager.persist).toHaveBeenCalled();
+  });
+
+  it("does not double-persist when multiple bindings share the same account", async () => {
+    const mkBinding = (conversationId: string) => ({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId,
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    });
+    listBindingsForAccountMock.mockReturnValue([mkBinding("$t1"), mkBinding("$t2")]);
+    removeBindingRecordMock.mockReturnValue(true);
+    getManagerMock.mockReturnValue(mockManager);
+    mockManager.persist.mockResolvedValue(undefined);
+
+    await handleMatrixSubagentEnded({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+    });
+
+    // persist must be called exactly once per unique accountId, not once per binding
+    expect(mockManager.persist).toHaveBeenCalledTimes(1);
+  });
+});
+
+describe("handleMatrixSubagentDeliveryTarget", () => {
+  beforeEach(() => {
+    listAllBindingsMock.mockReset();
+    listBindingsForAccountMock.mockReset();
+  });
+
+  it("returns undefined when expectsCompletionMessage is false", () => {
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops" },
+      expectsCompletionMessage: false,
+    });
+    expect(result).toBeUndefined();
+  });
+
+  it("returns undefined when requester channel is not matrix", () => {
+    listBindingsForAccountMock.mockReturnValue([]);
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "slack", accountId: "ops" },
+      expectsCompletionMessage: true,
+    });
+    expect(result).toBeUndefined();
+  });
+
+  it("returns undefined when no bindings match the child session key", () => {
+    listBindingsForAccountMock.mockReturnValue([
+      {
+        targetSessionKey: "agent:ops:subagent:OTHER",
+        targetKind: "subagent",
+        accountId: "ops",
+        conversationId: "$thread",
+        parentConversationId: "!room:example",
+        boundAt: 0,
+        lastActivityAt: 0,
+      },
+    ]);
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops" },
+      expectsCompletionMessage: true,
+    });
+    expect(result).toBeUndefined();
+  });
+
+  it("returns origin with threadId when binding has a distinct parentConversationId", () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread123",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops", threadId: "$thread123" },
+      expectsCompletionMessage: true,
+    });
+
+    expect(result).toEqual({
+      origin: {
+        channel: "matrix",
+        accountId: "ops",
+        to: "room:!room:example",
+        threadId: "$thread123",
+      },
+    });
+  });
+
+  it("returns origin without threadId when conversationId equals parentConversationId", () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "!room:example",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops" },
+      expectsCompletionMessage: true,
+    });
+
+    expect(result).toEqual({
+      origin: {
+        channel: "matrix",
+        accountId: "ops",
+        to: "room:!room:example",
+      },
+    });
+    expect(result?.origin).not.toHaveProperty("threadId");
+  });
+
+  it("returns origin without threadId when binding has no parentConversationId", () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops" },
+      expectsCompletionMessage: true,
+    });
+
+    expect(result).toEqual({
+      origin: {
+        channel: "matrix",
+        accountId: "ops",
+        to: "room:!room:example",
+      },
+    });
+  });
+
+  it("falls back to the single binding when requesterOrigin threadId does not match any binding", () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread123",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listBindingsForAccountMock.mockReturnValue([binding]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops", threadId: "$threadOTHER" },
+      expectsCompletionMessage: true,
+    });
+
+    // No threadId match, but single binding → falls back to it
+    expect(result).toEqual({
+      origin: {
+        channel: "matrix",
+        accountId: "ops",
+        to: "room:!room:example",
+        threadId: "$thread123",
+      },
+    });
+  });
+
+  it("returns undefined when multiple bindings exist and threadId matches none", () => {
+    const mkBinding = (threadId: string) => ({
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: threadId,
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    });
+    listBindingsForAccountMock.mockReturnValue([mkBinding("$t1"), mkBinding("$t2")]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix", accountId: "ops", threadId: "$tNONE" },
+      expectsCompletionMessage: true,
+    });
+
+    expect(result).toBeUndefined();
+  });
+
+  it("uses listAllBindings when requesterOrigin has no accountId", () => {
+    const binding = {
+      targetSessionKey: "agent:ops:subagent:child",
+      targetKind: "subagent",
+      accountId: "ops",
+      conversationId: "$thread123",
+      parentConversationId: "!room:example",
+      boundAt: 0,
+      lastActivityAt: 0,
+    };
+    listAllBindingsMock.mockReturnValue([binding]);
+
+    const result = handleMatrixSubagentDeliveryTarget({
+      childSessionKey: "agent:ops:subagent:child",
+      requesterOrigin: { channel: "matrix" },
+      expectsCompletionMessage: true,
+    });
+
+    expect(listAllBindingsMock).toHaveBeenCalled();
+    expect(listBindingsForAccountMock).not.toHaveBeenCalled();
+    expect(result).toBeDefined();
+  });
+});
diff --git a/extensions/matrix/src/matrix/subagent-hooks.ts b/extensions/matrix/src/matrix/subagent-hooks.ts
new file mode 100644
index 00000000000..075c1b4f014
--- /dev/null
+++ b/extensions/matrix/src/matrix/subagent-hooks.ts
@@ -0,0 +1,256 @@
+import { getSessionBindingService } from "openclaw/plugin-sdk/conversation-binding-runtime";
+import type { OpenClawPluginApi } from "openclaw/plugin-sdk/core";
+import { normalizeOptionalString } from "openclaw/plugin-sdk/text-runtime";
+import { findMatrixAccountConfig, resolveMatrixBaseConfig } from "./account-config.js";
+import { resolveMatrixTargetIdentity } from "./target-ids.js";
+import {
+  getMatrixThreadBindingManager,
+  listAllBindings,
+  listBindingsForAccount,
+  removeBindingRecord,
+} from "./thread-bindings-shared.js";
+
+type MatrixSubagentSpawningEvent = {
+  threadRequested: boolean;
+  requester?: {
+    channel?: string;
+    accountId?: string;
+    to?: string;
+    threadId?: string | number;
+  };
+  childSessionKey: string;
+  agentId: string;
+  label?: string;
+};
+
+type MatrixSubagentEndedEvent = {
+  targetSessionKey: string;
+  targetKind: string;
+  accountId?: string;
+};
+
+type MatrixSubagentDeliveryTargetEvent = {
+  childSessionKey: string;
+  requesterOrigin?: {
+    channel?: string;
+    accountId?: string;
+    to?: string;
+    threadId?: string | number;
+  };
+  expectsCompletionMessage: boolean;
+};
+
+type SpawningResult =
+  | { status: "ok"; threadBindingReady?: boolean }
+  | { status: "error"; error: string };
+
+type DeliveryTargetResult = {
+  origin: {
+    channel: string;
+    accountId: string;
+    to: string;
+    threadId?: string;
+  };
+};
+
+function summarizeError(err: unknown): string {
+  if (err instanceof Error) {
+    return err.message;
+  }
+  if (typeof err === "string") {
+    return err;
+  }
+  return "error";
+}
+
+function resolveThreadBindingFlags(
+  api: OpenClawPluginApi,
+  accountId?: string,
+): { enabled: boolean; spawnSubagentSessions: boolean } {
+  const matrix = resolveMatrixBaseConfig(api.config);
+  const baseThreadBindings = matrix.threadBindings;
+  const accountThreadBindings = accountId
+    ? findMatrixAccountConfig(api.config, accountId)?.threadBindings
+    : undefined;
+  return {
+    enabled:
+      accountThreadBindings?.enabled ??
+      baseThreadBindings?.enabled ??
+      api.config.session?.threadBindings?.enabled ??
+      true,
+    spawnSubagentSessions:
+      accountThreadBindings?.spawnSubagentSessions ??
+      baseThreadBindings?.spawnSubagentSessions ??
+      false,
+  };
+}
+
+export async function handleMatrixSubagentSpawning(
+  api: OpenClawPluginApi,
+  event: MatrixSubagentSpawningEvent,
+): Promise<SpawningResult | undefined> {
+  if (!event.threadRequested) {
+    return undefined;
+  }
+  const channel = event.requester?.channel?.trim().toLowerCase();
+  if (channel !== "matrix") {
+    return undefined;
+  }
+
+  const accountId = normalizeOptionalString(event.requester?.accountId) || undefined;
+  const flags = resolveThreadBindingFlags(api, accountId);
+
+  if (!flags.enabled) {
+    return {
+      status: "error",
+      error:
+        "Matrix thread bindings are disabled (set channels.matrix.threadBindings.enabled=true to override for this account, or session.threadBindings.enabled=true globally).",
+    };
+  }
+  if (!flags.spawnSubagentSessions) {
+    return {
+      status: "error",
+      error:
+        "Matrix thread-bound subagent spawns are disabled for this account (set channels.matrix.threadBindings.spawnSubagentSessions=true to enable).",
+    };
+  }
+
+  // Resolve the raw Matrix room ID from the requester's `to` field
+  // (e.g. "room:!abc123:example.org" → "!abc123:example.org").
+  const rawTo = normalizeOptionalString(event.requester?.to) ?? "";
+  const matrixTarget = rawTo ? resolveMatrixTargetIdentity(rawTo) : null;
+  const roomId = matrixTarget?.kind === "room" ? matrixTarget.id : "";
+
+  if (!roomId) {
+    return {
+      status: "error",
+      error:
+        "Cannot create Matrix thread binding: no room target in spawn request (requester.to must be a Matrix room ID).",
+    };
+  }
+
+  const resolvedAccountId = accountId || "default";
+
+  // Verify the thread binding manager is running for this account. The manager
+  // holds the captured Matrix client the SessionBindingAdapter needs to send
+  // the intro message that bootstraps the thread.
+  const manager = getMatrixThreadBindingManager(resolvedAccountId);
+  if (!manager) {
+    return {
+      status: "error",
+      error: `No Matrix thread binding manager available for account "${resolvedAccountId}". Is the Matrix channel running?`,
+    };
+  }
+
+  try {
+    // placement="child" tells the Matrix SessionBindingAdapter to:
+    // 1. Send an intro message to the room, creating a new thread root event
+    // 2. Use the returned event ID as boundConversationId (the thread ID)
+    // 3. Register the binding record in the in-memory store and persist it
+    //
+    // We do NOT call setBindingRecord here — the adapter's bind() handles
+    // record creation, thread creation, and persistence atomically.
+    await getSessionBindingService().bind({
+      targetSessionKey: event.childSessionKey,
+      targetKind: "subagent",
+      conversation: {
+        channel: "matrix",
+        accountId: resolvedAccountId,
+        conversationId: roomId,
+      },
+      placement: "child",
+      metadata: {
+        agentId: event.agentId?.trim() || undefined,
+        label: normalizeOptionalString(event.label) || undefined,
+        boundBy: "system",
+      },
+    });
+  } catch (err) {
+    return {
+      status: "error",
+      error: `Matrix thread bind failed: ${summarizeError(err)}`,
+    };
+  }
+
+  return { status: "ok", threadBindingReady: true };
+}
+
+export async function handleMatrixSubagentEnded(event: MatrixSubagentEndedEvent): Promise<void> {
+  const accountId = normalizeOptionalString(event.accountId) || undefined;
+  // Use the targeted account list when available; fall back to a full scan
+  // so bindings are cleaned up even when accountId is absent.
+  const candidates = accountId ? listBindingsForAccount(accountId) : listAllBindings();
+  const matching = candidates.filter(
+    (entry) => entry.targetSessionKey === event.targetSessionKey && entry.targetKind === "subagent",
+  );
+  const affectedAccountIds = new Set<string>();
+  for (const binding of matching) {
+    if (removeBindingRecord(binding)) {
+      affectedAccountIds.add(binding.accountId);
+    }
+  }
+  // Flush each affected account's manager so removals are persisted to disk.
+  for (const acctId of affectedAccountIds) {
+    const manager = getMatrixThreadBindingManager(acctId);
+    await manager?.persist();
+  }
+}
+
+export function handleMatrixSubagentDeliveryTarget(
+  event: MatrixSubagentDeliveryTargetEvent,
+): DeliveryTargetResult | undefined {
+  if (!event.expectsCompletionMessage) {
+    return undefined;
+  }
+  const requesterChannel = event.requesterOrigin?.channel?.trim().toLowerCase();
+  if (requesterChannel !== "matrix") {
+    return undefined;
+  }
+
+  const requesterAccountId = normalizeOptionalString(event.requesterOrigin?.accountId);
+  const requesterThreadId =
+    event.requesterOrigin?.threadId != null && event.requesterOrigin.threadId !== ""
+      ? String(event.requesterOrigin.threadId).trim()
+      : "";
+
+  // Search the targeted account when available; otherwise scan all accounts.
+  const candidates = requesterAccountId
+    ? listBindingsForAccount(requesterAccountId)
+    : listAllBindings();
+  const bindings = candidates.filter(
+    (entry) => entry.targetSessionKey === event.childSessionKey && entry.targetKind === "subagent",
+  );
+  if (bindings.length === 0) {
+    return undefined;
+  }
+
+  let binding: (typeof bindings)[number] | undefined;
+  if (requesterThreadId) {
+    binding = bindings.find(
+      (entry) =>
+        entry.conversationId === requesterThreadId &&
+        (!requesterAccountId || entry.accountId === requesterAccountId),
+    );
+  }
+  if (!binding && bindings.length === 1) {
+    binding = bindings[0];
+  }
+  if (!binding) {
+    return undefined;
+  }
+
+  const roomId = binding.parentConversationId ?? binding.conversationId;
+  const threadId =
+    binding.parentConversationId && binding.parentConversationId !== binding.conversationId
+      ? binding.conversationId
+      : undefined;
+
+  return {
+    origin: {
+      channel: "matrix",
+      accountId: binding.accountId,
+      to: `room:${roomId}`,
+      ...(threadId ? { threadId } : {}),
+    },
+  };
+}
diff --git a/extensions/matrix/src/matrix/thread-bindings-shared.ts b/extensions/matrix/src/matrix/thread-bindings-shared.ts
index 6c63a731490..298f7757782 100644
--- a/extensions/matrix/src/matrix/thread-bindings-shared.ts
+++ b/extensions/matrix/src/matrix/thread-bindings-shared.ts
@@ -40,6 +40,7 @@ export type MatrixThreadBindingManager = {
     targetSessionKey: string;
     maxAgeMs: number;
   }) => MatrixThreadBindingRecord[];
+  persist: () => Promise<void>;
   stop: () => void;
 };
 
@@ -135,6 +136,10 @@ export function listBindingsForAccount(accountId: string): MatrixThreadBindingRe
   );
 }
 
+export function listAllBindings(): MatrixThreadBindingRecord[] {
+  return [...BINDINGS_BY_ACCOUNT_CONVERSATION.values()];
+}
+
 export function getMatrixThreadBindingManagerEntry(
   accountId: string,
 ): MatrixThreadBindingManagerCacheEntry | null {
diff --git a/extensions/matrix/src/matrix/thread-bindings.ts b/extensions/matrix/src/matrix/thread-bindings.ts
index 397fc67db4e..6544967bdaa 100644
--- a/extensions/matrix/src/matrix/thread-bindings.ts
+++ b/extensions/matrix/src/matrix/thread-bindings.ts
@@ -292,6 +292,7 @@ export async function createMatrixThreadBindingManager(params: {
     accountId: params.accountId,
     getIdleTimeoutMs: () => defaults.idleTimeoutMs,
     getMaxAgeMs: () => defaults.maxAgeMs,
+    persist,
     getByConversation: ({ conversationId, parentConversationId }) =>
       listBindingsForAccount(params.accountId).find((entry) => {
         if (entry.conversationId !== conversationId.trim()) {