feat: add /new command (#374)

Co-authored-by: Letta <noreply@letta.com>

src/cli/App.tsx

@@ -18,7 +18,7 @@ import { prefetchAvailableModelHandles } from "../agent/available-models";
 import { getResumeData } from "../agent/check-approval";
 import { getClient } from "../agent/client";
 import { getCurrentAgentId, setCurrentAgentId } from "../agent/context";
-import type { AgentProvenance } from "../agent/create";
+import { type AgentProvenance, createAgent } from "../agent/create";
 import { sendMessageStream } from "../agent/message";
 import { SessionStats } from "../agent/stats";
 import type { ApprovalContext } from "../permissions/analyzer";
@@ -62,6 +62,7 @@ import { McpSelector } from "./components/McpSelector";
 import { MemoryViewer } from "./components/MemoryViewer";
 import { MessageSearch } from "./components/MessageSearch";
 import { ModelSelector } from "./components/ModelSelector";
+import { NewAgentDialog } from "./components/NewAgentDialog";
 import { OAuthCodeDialog } from "./components/OAuthCodeDialog";
 import { PinDialog, validateAgentName } from "./components/PinDialog";
 import { PlanModeDialog } from "./components/PlanModeDialog";
@@ -436,6 +437,7 @@ export default function App({
     | "feedback"
     | "memory"
     | "pin"
+    | "new"
     | "mcp"
     | "help"
     | "oauth"
@@ -1666,6 +1668,18 @@ export default function App({
       setCommandRunning(true);
 
       const inputCmd = "/pinned";
+      const cmdId = uid("cmd");
+
+      // Show loading indicator while switching
+      buffersRef.current.byId.set(cmdId, {
+        kind: "command",
+        id: cmdId,
+        input: inputCmd,
+        output: "Switching agent...",
+        phase: "running",
+      });
+      buffersRef.current.order.push(cmdId);
+      refreshDerived();
 
       try {
         const client = await getClient();
@@ -1731,6 +1745,7 @@ export default function App({
           hasBackfilledRef.current = true;
         } else {
           setStaticItems([successItem]);
+          setLines(toLines(buffersRef.current));
         }
       } catch (error) {
         const errorDetails = formatErrorDetails(error, agentId);
@@ -1752,6 +1767,96 @@ export default function App({
     [refreshDerived, agentId, agentName, setCommandRunning],
   );
 
+  // Handle creating a new agent and switching to it
+  const handleCreateNewAgent = useCallback(
+    async (name: string) => {
+      // Close dialog immediately
+      setActiveOverlay(null);
+
+      // Lock input for async operation
+      setCommandRunning(true);
+
+      const inputCmd = "/new";
+      const cmdId = uid("cmd");
+
+      // Show "Creating..." status while we wait
+      buffersRef.current.byId.set(cmdId, {
+        kind: "command",
+        id: cmdId,
+        input: inputCmd,
+        output: `Creating agent "${name}"...`,
+        phase: "running",
+      });
+      buffersRef.current.order.push(cmdId);
+      refreshDerived();
+
+      try {
+        // Create the new agent
+        const { agent } = await createAgent(name);
+
+        // Update project settings with new agent
+        await updateProjectSettings({ lastAgent: agent.id });
+
+        // Clear current transcript and static items
+        buffersRef.current.byId.clear();
+        buffersRef.current.order = [];
+        buffersRef.current.tokenCount = 0;
+        emittedIdsRef.current.clear();
+        setStaticItems([]);
+        setStaticRenderEpoch((e) => e + 1);
+
+        // Reset turn counter for memory reminders
+        turnCountRef.current = 0;
+
+        // Update agent state
+        agentIdRef.current = agent.id;
+        setAgentId(agent.id);
+        setAgentState(agent);
+        setAgentName(agent.name);
+        setLlmConfig(agent.llm_config);
+
+        // Build success message with hints
+        const agentUrl = `https://app.letta.com/projects/default-project/agents/${agent.id}`;
+        const successOutput = [
+          `Created **${agent.name || agent.id}** (use /pin to save)`,
+          `⎿  ${agentUrl}`,
+          `⎿  Tip: use /init to initialize your agent's memory system!`,
+        ].join("\n");
+
+        const separator = {
+          kind: "separator" as const,
+          id: uid("sep"),
+        };
+        const successItem: StaticItem = {
+          kind: "command",
+          id: uid("cmd"),
+          input: inputCmd,
+          output: successOutput,
+          phase: "finished",
+          success: true,
+        };
+
+        setStaticItems([separator, successItem]);
+        // Sync lines display after clearing buffers
+        setLines(toLines(buffersRef.current));
+      } catch (error) {
+        const errorDetails = formatErrorDetails(error, agentId);
+        buffersRef.current.byId.set(cmdId, {
+          kind: "command",
+          id: cmdId,
+          input: inputCmd,
+          output: `Failed to create agent: ${errorDetails}`,
+          phase: "finished",
+          success: false,
+        });
+        refreshDerived();
+      } finally {
+        setCommandRunning(false);
+      }
+    },
+    [refreshDerived, agentId, setCommandRunning],
+  );
+
   // Handle bash mode command submission
   // Uses the same shell runner as the Bash tool for consistency
   const handleBashSubmit = useCallback(
@@ -2659,6 +2764,12 @@ export default function App({
           return { submitted: true };
         }
 
+        // Special handling for /new command - create new agent dialog
+        if (msg.trim() === "/new") {
+          setActiveOverlay("new");
+          return { submitted: true };
+        }
+
         // Special handling for /pin command - pin current agent to project (or globally with -g)
         if (msg.trim() === "/pin" || msg.trim().startsWith("/pin ")) {
           const argsStr = msg.trim().slice(4).trim();
@@ -5024,6 +5135,14 @@ Plan file path: ${planFilePath}`;
               />
             )}
 
+            {/* New Agent Dialog - for naming new agent before creation */}
+            {activeOverlay === "new" && (
+              <NewAgentDialog
+                onSubmit={handleCreateNewAgent}
+                onCancel={closeOverlay}
+              />
+            )}
+
             {/* Pin Dialog - for naming agent before pinning */}
             {activeOverlay === "pin" && (
               <PinDialog

src/cli/commands/registry.ts

@@ -167,6 +167,13 @@ export const commands: Record<string, Command> = {
       return "Opening pinned agents...";
     },
   },
+  "/new": {
+    desc: "Create a new agent and switch to it",
+    handler: () => {
+      // Handled specially in App.tsx
+      return "Creating new agent...";
+    },
+  },
   "/subagents": {
     desc: "Manage custom subagents",
     handler: () => {

src/cli/components/NewAgentDialog.tsx

@@ -0,0 +1,84 @@
+import { Box, Text, useInput } from "ink";
+import { useState } from "react";
+import { DEFAULT_AGENT_NAME } from "../../constants";
+import { colors } from "./colors";
+import { PasteAwareTextInput } from "./PasteAwareTextInput";
+import { validateAgentName } from "./PinDialog";
+
+interface NewAgentDialogProps {
+  onSubmit: (name: string) => void;
+  onCancel: () => void;
+}
+
+export function NewAgentDialog({ onSubmit, onCancel }: NewAgentDialogProps) {
+  const [nameInput, setNameInput] = useState("");
+  const [error, setError] = useState("");
+
+  useInput((_, key) => {
+    if (key.escape) {
+      onCancel();
+    }
+  });
+
+  const handleNameSubmit = (text: string) => {
+    const trimmed = text.trim();
+
+    // Empty input = use default name
+    if (!trimmed) {
+      onSubmit(DEFAULT_AGENT_NAME);
+      return;
+    }
+
+    const validationError = validateAgentName(trimmed);
+    if (validationError) {
+      setError(validationError);
+      return;
+    }
+
+    onSubmit(trimmed);
+  };
+
+  return (
+    <Box flexDirection="column" paddingY={1}>
+      <Box marginBottom={1}>
+        <Text color={colors.approval.header} bold>
+          Create new agent
+        </Text>
+      </Box>
+
+      <Box marginBottom={1}>
+        <Text dimColor>
+          Enter a name for your new agent, or press Enter for default.
+        </Text>
+      </Box>
+
+      <Box flexDirection="column" marginBottom={1}>
+        <Box marginBottom={1}>
+          <Text>Agent name:</Text>
+        </Box>
+        <Box>
+          <Text color={colors.approval.header}>&gt; </Text>
+          <PasteAwareTextInput
+            value={nameInput}
+            onChange={(val) => {
+              setNameInput(val);
+              setError("");
+            }}
+            onSubmit={handleNameSubmit}
+            placeholder={DEFAULT_AGENT_NAME}
+          />
+        </Box>
+      </Box>
+
+      {error && (
+        <Box marginBottom={1}>
+          <Text color="red">{error}</Text>
+        </Box>
+      )}
+
+      <Box>
+        <Text dimColor>Press Enter to create • Esc to cancel</Text>
+      </Box>
+    </Box>
+  );
+}