Add register_group IPC command for dynamic group registration

Main agent can now register new groups via MCP tool without restart.
Host updates both in-memory state and JSON file, creates group folders.
Authorization enforced at both agent and host level.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

container/agent-runner/src/ipc-mcp.ts

@@ -276,6 +276,45 @@ SCHEDULE VALUE FORMAT (all times are LOCAL timezone):
             }]
           };
         }
+      ),
+
+      tool(
+        'register_group',
+        `Register a new WhatsApp group so the agent can respond to messages there. Main group only.
+
+Use available_groups.json to find the JID for a group. The folder name should be lowercase with hyphens (e.g., "family-chat").`,
+        {
+          jid: z.string().describe('The WhatsApp JID (e.g., "120363336345536173@g.us")'),
+          name: z.string().describe('Display name for the group'),
+          folder: z.string().describe('Folder name for group files (lowercase, hyphens, e.g., "family-chat")'),
+          trigger: z.string().describe('Trigger word (e.g., "@Andy")')
+        },
+        async (args) => {
+          if (!isMain) {
+            return {
+              content: [{ type: 'text', text: 'Only the main group can register new groups.' }],
+              isError: true
+            };
+          }
+
+          const data = {
+            type: 'register_group',
+            jid: args.jid,
+            name: args.name,
+            folder: args.folder,
+            trigger: args.trigger,
+            timestamp: new Date().toISOString()
+          };
+
+          writeIpcFile(TASKS_DIR, data);
+
+          return {
+            content: [{
+              type: 'text',
+              text: `Group "${args.name}" registered. It will start receiving messages immediately.`
+            }]
+          };
+        }
       )
     ]
   });

src/index.ts

@@ -61,6 +61,17 @@ function saveState(): void {
   saveJson(path.join(DATA_DIR, 'sessions.json'), sessions);
 }
 
+function registerGroup(jid: string, group: RegisteredGroup): void {
+  registeredGroups[jid] = group;
+  saveJson(path.join(DATA_DIR, 'registered_groups.json'), registeredGroups);
+
+  // Create group folder
+  const groupDir = path.join(DATA_DIR, '..', 'groups', group.folder);
+  fs.mkdirSync(path.join(groupDir, 'logs'), { recursive: true });
+
+  logger.info({ jid, name: group.name, folder: group.folder }, 'Group registered');
+}
+
 /**
  * Sync group metadata from WhatsApp.
  * Fetches all participating groups and stores their names in the database.
@@ -306,6 +317,12 @@ async function processTaskIpc(
     context_mode?: string;
     groupFolder?: string;
     chatJid?: string;
+    // For register_group
+    jid?: string;
+    name?: string;
+    folder?: string;
+    trigger?: string;
+    containerConfig?: RegisteredGroup['containerConfig'];
   },
   sourceGroup: string,  // Verified identity from IPC directory
   isMain: boolean       // Verified from directory path
@@ -431,6 +448,25 @@ async function processTaskIpc(
       }
       break;
 
+    case 'register_group':
+      // Only main group can register new groups
+      if (!isMain) {
+        logger.warn({ sourceGroup }, 'Unauthorized register_group attempt blocked');
+        break;
+      }
+      if (data.jid && data.name && data.folder && data.trigger) {
+        registerGroup(data.jid, {
+          name: data.name,
+          folder: data.folder,
+          trigger: data.trigger,
+          added_at: new Date().toISOString(),
+          containerConfig: data.containerConfig
+        });
+      } else {
+        logger.warn({ data }, 'Invalid register_group request - missing required fields');
+      }
+      break;
+
     default:
       logger.warn({ type: data.type }, 'Unknown IPC task type');
   }