🐛 fix: slove the agents_documents will coverd the systemRole (#13667)

fix: slove the agents_documents will coverd the systemRole

packages/context-engine/src/providers/SystemRoleInjector.ts

@@ -1,6 +1,6 @@
 import debug from 'debug';
 
-import { BaseProvider } from '../base/BaseProvider';
+import { BaseSystemRoleProvider } from '../base/BaseSystemRoleProvider';
 import type { PipelineContext, ProcessorOptions } from '../types';
 
 declare module '../types' {
@@ -18,9 +18,13 @@ export interface SystemRoleInjectorConfig {
 
 /**
  * System Role Injector
- * Responsible for injecting system role messages at the beginning of the conversation
+ *
+ * Injects the agent's system role into the system message. If a system message
+ * already exists (e.g. created by AgentDocumentBeforeSystemInjector), the
+ * system role is appended to it via the BaseSystemRoleProvider join logic;
+ * otherwise a new system message is created.
  */
-export class SystemRoleInjector extends BaseProvider {
+export class SystemRoleInjector extends BaseSystemRoleProvider {
   readonly name = 'SystemRoleInjector';
 
   constructor(
@@ -30,40 +34,18 @@ export class SystemRoleInjector extends BaseProvider {
     super(options);
   }
 
-  protected async doProcess(context: PipelineContext): Promise<PipelineContext> {
-    const clonedContext = this.cloneContext(context);
-
-    // Skip injection if no system role is configured
-    if (!this.config.systemRole || this.config.systemRole.trim() === '') {
+  protected buildSystemRoleContent(_context: PipelineContext): string | null {
+    const systemRole = this.config.systemRole;
+    if (!systemRole || systemRole.trim() === '') {
       log('No system role configured, skipping injection');
-      return this.markAsExecuted(clonedContext);
+      return null;
     }
 
-    // Check if system role already exists at the beginning
-    const hasExistingSystemRole =
-      clonedContext.messages.length > 0 && clonedContext.messages[0].role === 'system';
+    return systemRole;
+  }
 
-    if (hasExistingSystemRole) {
-      log('System role already exists, skipping injection');
-      return this.markAsExecuted(clonedContext);
-    }
-
-    // Inject system role at the beginning
-    const systemMessage = {
-      content: this.config.systemRole,
-      createdAt: Date.now(),
-      id: `system-${Date.now()}`,
-      role: 'system' as const,
-      updatedAt: Date.now(),
-    };
-
-    clonedContext.messages.unshift(systemMessage);
-
-    // Update metadata
-    clonedContext.metadata.systemRoleInjected = true;
-
-    log(`System role injected: "${this.config.systemRole.slice(0, 50)}..."`);
-
-    return this.markAsExecuted(clonedContext);
+  protected onInjected(context: PipelineContext, content: string): void {
+    context.metadata.systemRoleInjected = true;
+    log(`System role injected: "${content.slice(0, 50)}..."`);
   }
 }

packages/context-engine/src/providers/__tests__/SystemRoleInjector.test.ts

@@ -86,7 +86,7 @@ describe('SystemRoleInjector', () => {
     expect(result.metadata.systemRoleInjected).toBeUndefined();
   });
 
-  it('should skip injection when system role already exists', async () => {
+  it('should append system role to existing system message', async () => {
     const provider = new SystemRoleInjector({
       systemRole: 'You are a helpful assistant.',
     });
@@ -125,8 +125,62 @@ describe('SystemRoleInjector', () => {
     const result = await provider.process(context);
 
     expect(result.messages).toHaveLength(2);
-    expect(result.messages[0].content).toBe('Existing system role');
-    expect(result.metadata.systemRoleInjected).toBeUndefined();
+    expect(result.messages[0].role).toBe('system');
+    expect(result.messages[0].content).toBe('Existing system role\n\nYou are a helpful assistant.');
+    expect(result.messages[1].role).toBe('user');
+    expect(result.metadata.systemRoleInjected).toBe(true);
+  });
+
+  it('should append systemRole after AgentDocumentBeforeSystemInjector output (regression for LOBE-6892)', async () => {
+    const provider = new SystemRoleInjector({
+      systemRole: '你是一个思维活跃的工程师，擅长 Python、JavaScript、Docker、SQL。',
+    });
+
+    const beforeSystemDocContent =
+      '<agent_documents>\n<document title="rules">always reply in Chinese</document>\n</agent_documents>';
+
+    const context = {
+      initialState: {
+        messages: [],
+        model: 'gpt-4',
+        provider: 'openai',
+        systemRole: '',
+        tools: [],
+      },
+      messages: [
+        // Simulates the message that AgentDocumentBeforeSystemInjector unshifts
+        {
+          id: 'agent-doc-before-system-1700000000000',
+          role: 'system',
+          content: beforeSystemDocContent,
+          createdAt: Date.now(),
+          updatedAt: Date.now(),
+        },
+        {
+          id: '1',
+          role: 'user',
+          content: 'Hello',
+          createdAt: Date.now(),
+          updatedAt: Date.now(),
+        },
+      ],
+      metadata: {
+        model: 'gpt-4',
+        maxTokens: 4096,
+      },
+      isAborted: false,
+    };
+
+    const result = await provider.process(context);
+
+    expect(result.messages).toHaveLength(2);
+    expect(result.messages[0].role).toBe('system');
+    // doc content stays in front, systemRole appended after with \n\n separator
+    expect(result.messages[0].content).toBe(
+      `${beforeSystemDocContent}\n\n你是一个思维活跃的工程师，擅长 Python、JavaScript、Docker、SQL。`,
+    );
+    expect(result.messages[1].role).toBe('user');
+    expect(result.metadata.systemRoleInjected).toBe(true);
   });
 
   it('should handle whitespace-only system role', async () => {