Enable & disable agents (#16225)

packages/core/src/agents/a2a-client-manager.ts

@@ -64,7 +64,7 @@ export class A2AClientManager {
     agentCardUrl: string,
     authHandler?: AuthenticationHandler,
   ): Promise<AgentCard> {
-    if (this.clients.has(name)) {
+    if (this.clients.has(name) && this.agentCards.has(name)) {
       throw new Error(`Agent with name '${name}' is already loaded.`);
     }
 

packages/core/src/agents/registry.ts

@@ -69,6 +69,7 @@ export class AgentRegistry {
    */
   async reload(): Promise<void> {
     A2AClientManager.getInstance().clearCache();
+    await this.config.reloadAgents();
     this.agents.clear();
     await this.loadAgents();
     coreEvents.emitAgentsRefreshed();
@@ -143,9 +144,14 @@ export class AgentRegistry {
   private loadBuiltInAgents(): void {
     const investigatorSettings = this.config.getCodebaseInvestigatorSettings();
     const cliHelpSettings = this.config.getCliHelpAgentSettings();
+    const agentsSettings = this.config.getAgentsSettings();
+    const agentsOverrides = agentsSettings.overrides ?? {};
 
-    // Only register the agent if it's enabled in the settings.
-    if (investigatorSettings?.enabled) {
+    // Only register the agent if it's enabled in the settings and not explicitly disabled via overrides.
+    if (
+      investigatorSettings?.enabled &&
+      !agentsOverrides[CodebaseInvestigatorAgent.name]?.disabled
+    ) {
       let model;
       const settingsModel = investigatorSettings.model;
       // Check if the user explicitly set a model in the settings.
@@ -189,8 +195,11 @@ export class AgentRegistry {
       this.registerLocalAgent(agentDef);
     }
 
-    // Register the CLI help agent if it's explicitly enabled.
-    if (cliHelpSettings.enabled) {
+    // Register the CLI help agent if it's explicitly enabled and not explicitly disabled via overrides.
+    if (
+      cliHelpSettings.enabled &&
+      !agentsOverrides[CliHelpAgent.name]?.disabled
+    ) {
       this.registerLocalAgent(CliHelpAgent(this.config));
     }
   }

packages/core/src/config/config.ts

@@ -387,6 +387,7 @@ export interface ConfigParameters {
   onReload?: () => Promise<{
     disabledSkills?: string[];
     adminSkillsEnabled?: boolean;
+    agents?: AgentSettings;
   }>;
 }
 
@@ -518,11 +519,12 @@ export class Config {
     | (() => Promise<{
         disabledSkills?: string[];
         adminSkillsEnabled?: boolean;
+        agents?: AgentSettings;
       }>)
     | undefined;
 
   private readonly enableAgents: boolean;
-  private readonly agents: AgentSettings;
+  private agents: AgentSettings;
   private readonly skillsSupport: boolean;
   private disabledSkills: string[];
   private readonly adminSkillsEnabled: boolean;
@@ -1634,6 +1636,18 @@ export class Config {
     await this.updateSystemInstructionIfInitialized();
   }
 
+  /**
+   * Reloads agent settings.
+   */
+  async reloadAgents(): Promise<void> {
+    if (this.onReload) {
+      const refreshed = await this.onReload();
+      if (refreshed.agents) {
+        this.agents = refreshed.agents;
+      }
+    }
+  }
+
   isInteractive(): boolean {
     return this.interactive;
   }