feat: cw task add CLI command + {AGENT_ID} prompt placeholder

- Add `createTaskForAgent` tRPC mutation: resolves agent → task → phase, creates sibling task
- Add `cw task add <name> --agent-id <id>` CLI command
- Replace `{AGENT_ID}` and `{AGENT_NAME}` placeholders in writeInputFiles() before flushing
- Update docs/agent.md and docs/cli-config.md

apps/server/agent/file-io.ts

@@ -282,6 +282,17 @@ export async function writeInputFiles(options: WriteInputFilesOptions): Promise<
     });
   }
 
+  // Replace agent placeholders in all content before writing
+  const placeholders: Record<string, string> = {
+    '{AGENT_ID}': options.agentId ?? '',
+    '{AGENT_NAME}': options.agentName ?? '',
+  };
+  for (const w of writes) {
+    for (const [token, value] of Object.entries(placeholders)) {
+      w.content = w.content.replaceAll(token, value);
+    }
+  }
+
   // Flush all file writes in parallel — yields the event loop between I/O ops
   await Promise.all(writes.map(w => writeFile(w.path, w.content, 'utf-8')));
 

apps/server/cli/index.ts

@@ -426,6 +426,32 @@ export function createCli(serverHandler?: (port?: number) => Promise<void>): Com
       }
     });
 
+  // cw task add <name> --agent-id <agentId>
+  taskCommand
+    .command('add <name>')
+    .description('Create a sibling task in the agent\'s current phase')
+    .requiredOption('--agent-id <agentId>', 'Agent ID creating the task')
+    .option('--description <description>', 'Task description')
+    .option('--category <category>', 'Task category (execute, research, verify, ...)')
+    .action(async (name: string, options: { agentId: string; description?: string; category?: string }) => {
+      try {
+        const client = createDefaultTrpcClient();
+        const task = await client.createTaskForAgent.mutate({
+          agentId: options.agentId,
+          name,
+          description: options.description,
+          category: options.category as 'execute' | undefined,
+        });
+        console.log(`Created task: ${task.name}`);
+        console.log(`  ID: ${task.id}`);
+        console.log(`  Phase: ${task.phaseId}`);
+        console.log(`  Status: ${task.status}`);
+      } catch (error) {
+        console.error('Failed to create task:', (error as Error).message);
+        process.exit(1);
+      }
+    });
+
   // Message command group
   const messageCommand = program
     .command('message')

apps/server/trpc/routers/task.ts

@@ -11,6 +11,7 @@ import {
   requirePhaseRepository,
   requireDispatchManager,
   requireChangeSetRepository,
+  requireAgentManager,
 } from './_helpers.js';
 
 export function taskProcedures(publicProcedure: ProcedureBuilder) {
@@ -213,5 +214,55 @@ export function taskProcedures(publicProcedure: ProcedureBuilder) {
         return edges;
       }),
 
+    createTaskForAgent: publicProcedure
+      .input(z.object({
+        agentId: z.string().min(1),
+        name: z.string().min(1),
+        description: z.string().optional(),
+        category: z.enum(['execute', 'research', 'discuss', 'plan', 'detail', 'refine', 'verify', 'merge', 'review']).optional(),
+      }))
+      .mutation(async ({ ctx, input }) => {
+        const agentManager = requireAgentManager(ctx);
+        const taskRepository = requireTaskRepository(ctx);
+
+        const agent = await agentManager.get(input.agentId);
+        if (!agent) {
+          throw new TRPCError({
+            code: 'NOT_FOUND',
+            message: `Agent '${input.agentId}' not found`,
+          });
+        }
+        if (!agent.taskId) {
+          throw new TRPCError({
+            code: 'BAD_REQUEST',
+            message: `Agent '${agent.name}' has no assigned task`,
+          });
+        }
+
+        const agentTask = await taskRepository.findById(agent.taskId);
+        if (!agentTask) {
+          throw new TRPCError({
+            code: 'NOT_FOUND',
+            message: `Agent's task '${agent.taskId}' not found`,
+          });
+        }
+        if (!agentTask.phaseId) {
+          throw new TRPCError({
+            code: 'BAD_REQUEST',
+            message: `Agent's task has no phase — cannot create sibling task`,
+          });
+        }
+
+        return taskRepository.create({
+          phaseId: agentTask.phaseId,
+          initiativeId: agentTask.initiativeId,
+          name: input.name,
+          description: input.description ?? null,
+          category: input.category ?? 'execute',
+          type: 'auto',
+          status: 'pending',
+        });
+      }),
+
   };
 }