Context: extract extension host engine runtime

src/context-engine/registry.ts

@@ -1,5 +1,10 @@
-import type { OpenClawConfig } from "../config/config.js";
-import { defaultSlotIdForKey } from "../plugins/slots.js";
+import {
+  getExtensionHostContextEngineFactory,
+  listExtensionHostContextEngineIds,
+  registerExtensionHostContextEngine,
+  resolveExtensionHostContextEngine,
+  type ExtensionHostContextEngineFactory,
+} from "../extension-host/context-engine-runtime.js";
 import type { ContextEngine } from "./types.js";
 
 /**
@@ -97,18 +102,12 @@ export function registerContextEngine(
   return registerContextEngineForOwner(id, factory, PUBLIC_CONTEXT_ENGINE_OWNER);
 }
 
-/**
- * Return the factory for a registered engine, or undefined.
- */
 export function getContextEngineFactory(id: string): ContextEngineFactory | undefined {
   return getContextEngineRegistryState().engines.get(id)?.factory;
 }
 
-/**
- * List all registered engine ids.
- */
 export function listContextEngineIds(): string[] {
-  return [...getContextEngineRegistryState().engines.keys()];
+  return listExtensionHostContextEngineIds();
 }
 
 // ---------------------------------------------------------------------------

src/extension-host/context-engine-runtime.test.ts

@@ -0,0 +1,42 @@
+import { describe, expect, it } from "vitest";
+import type { ContextEngine } from "../context-engine/types.js";
+import {
+  getExtensionHostContextEngineFactory,
+  listExtensionHostContextEngineIds,
+  registerExtensionHostContextEngine,
+} from "./context-engine-runtime.js";
+
+class TestContextEngine implements ContextEngine {
+  readonly info = {
+    id: "host-test",
+    name: "Host Test",
+    version: "1.0.0",
+  };
+
+  async ingest() {
+    return { ingested: false };
+  }
+
+  async assemble(params: { messages: [] }) {
+    return { messages: params.messages, estimatedTokens: 0 };
+  }
+
+  async afterTurn() {}
+
+  async compact() {
+    return { ok: true, compacted: false, reason: "noop" };
+  }
+}
+
+describe("extension host context engine runtime", () => {
+  it("stores registered context-engine factories in the host-owned runtime", async () => {
+    const factory = () => new TestContextEngine();
+    registerExtensionHostContextEngine("host-test", factory);
+
+    expect(getExtensionHostContextEngineFactory("host-test")).toBe(factory);
+    expect(listExtensionHostContextEngineIds()).toContain("host-test");
+    expect(await getExtensionHostContextEngineFactory("host-test")?.()).toBeInstanceOf(
+      TestContextEngine,
+    );
+  });
+});

src/extension-host/context-engine-runtime.ts

@@ -0,0 +1,60 @@
+import type { OpenClawConfig } from "../config/config.js";
+import type { ContextEngine } from "../context-engine/types.js";
+import { defaultSlotIdForKey } from "../plugins/slots.js";
+
+export type ExtensionHostContextEngineFactory = () => ContextEngine | Promise<ContextEngine>;
+
+const CONTEXT_ENGINE_RUNTIME_STATE = Symbol.for("openclaw.contextEngineRegistryState");
+
+type ExtensionHostContextEngineRuntimeState = {
+  engines: Map<string, ExtensionHostContextEngineFactory>;
+};
+
+function getExtensionHostContextEngineRuntimeState(): ExtensionHostContextEngineRuntimeState {
+  const globalState = globalThis as typeof globalThis & {
+    [CONTEXT_ENGINE_RUNTIME_STATE]?: ExtensionHostContextEngineRuntimeState;
+  };
+  if (!globalState[CONTEXT_ENGINE_RUNTIME_STATE]) {
+    globalState[CONTEXT_ENGINE_RUNTIME_STATE] = {
+      engines: new Map<string, ExtensionHostContextEngineFactory>(),
+    };
+  }
+  return globalState[CONTEXT_ENGINE_RUNTIME_STATE];
+}
+
+export function registerExtensionHostContextEngine(
+  id: string,
+  factory: ExtensionHostContextEngineFactory,
+): void {
+  getExtensionHostContextEngineRuntimeState().engines.set(id, factory);
+}
+
+export function getExtensionHostContextEngineFactory(
+  id: string,
+): ExtensionHostContextEngineFactory | undefined {
+  return getExtensionHostContextEngineRuntimeState().engines.get(id);
+}
+
+export function listExtensionHostContextEngineIds(): string[] {
+  return [...getExtensionHostContextEngineRuntimeState().engines.keys()];
+}
+
+export async function resolveExtensionHostContextEngine(
+  config?: OpenClawConfig,
+): Promise<ContextEngine> {
+  const slotValue = config?.plugins?.slots?.contextEngine;
+  const engineId =
+    typeof slotValue === "string" && slotValue.trim()
+      ? slotValue.trim()
+      : defaultSlotIdForKey("contextEngine");
+
+  const factory = getExtensionHostContextEngineRuntimeState().engines.get(engineId);
+  if (!factory) {
+    throw new Error(
+      `Context engine "${engineId}" is not registered. ` +
+        `Available engines: ${listExtensionHostContextEngineIds().join(", ") || "(none)"}`,
+    );
+  }
+
+  return factory();
+}

src/extension-host/plugin-registry-registrations.ts

@@ -1,6 +1,5 @@
 import type { AnyAgentTool } from "../agents/tools/common.js";
 import type { ChannelPlugin } from "../channels/plugins/types.js";
-import { registerContextEngine as registerLegacyContextEngine } from "../context-engine/registry.js";
 import type { GatewayRequestHandler } from "../gateway/server-methods/types.js";
 import { registerInternalHook } from "../hooks/internal-hooks.js";
 import type { PluginRecord, PluginRegistry } from "../plugins/registry.js";
@@ -16,6 +15,7 @@ import type {
   OpenClawPluginToolFactory,
   PluginHookRegistration as TypedPluginHookRegistration,
 } from "../plugins/types.js";
+import { registerExtensionHostContextEngine } from "./context-engine-runtime.js";
 import {
   applyExtensionHostTypedHookPolicy,
   bridgeExtensionHostLegacyHooks,
@@ -307,7 +307,7 @@ export function createExtensionHostPluginRegistrationActions(params: {
   const registerContextEngine = (
     record: PluginRecord,
     engineId: string,
-    factory: Parameters<typeof registerLegacyContextEngine>[1],
+    factory: Parameters<typeof registerExtensionHostContextEngine>[1],
   ) => {
     const result = resolveExtensionContextEngineRegistration({
       engineId,
@@ -325,7 +325,7 @@ export function createExtensionHostPluginRegistrationActions(params: {
     }
     addExtensionContextEngineRegistration({
       entry: result.entry,
-      registerEngine: registerLegacyContextEngine,
+      registerEngine: registerExtensionHostContextEngine,
     });
   };
 

src/extension-host/registry-writes.ts

@@ -1,4 +1,3 @@
-import { registerContextEngine, type ContextEngineFactory } from "../context-engine/registry.js";
 import type { GatewayRequestHandler } from "../gateway/server-methods/types.js";
 import type {
   PluginChannelRegistration,
@@ -13,6 +12,10 @@ import type {
   PluginToolRegistration,
 } from "../plugins/registry.js";
 import type { PluginHookRegistration as TypedPluginHookRegistration } from "../plugins/types.js";
+import {
+  registerExtensionHostContextEngine,
+  type ExtensionHostContextEngineFactory,
+} from "./context-engine-runtime.js";
 import type {
   ExtensionHostChannelRegistration,
   ExtensionHostCliRegistration,
@@ -162,8 +165,8 @@ export function addExtensionCommandRegistration(params: {
 
 export function addExtensionContextEngineRegistration(params: {
   entry: ExtensionHostContextEngineRegistration;
-  registerEngine?: (engineId: string, factory: ContextEngineFactory) => void;
+  registerEngine?: (engineId: string, factory: ExtensionHostContextEngineFactory) => void;
 }): void {
-  const registerEngine = params.registerEngine ?? registerContextEngine;
+  const registerEngine = params.registerEngine ?? registerExtensionHostContextEngine;
   registerEngine(params.entry.engineId, params.entry.factory);
 }