feat(project): render create results as JSON and truncate task titles

src/components/ui/task-list/TaskList.test.tsx

@@ -55,6 +55,29 @@ describe("TaskList", () => {
     expect(frame).toContain("│ three");
   });
 
+  test("keeps a long title on one line without losing its glyph", () => {
+    const instance = render(<></>);
+    Object.defineProperty(instance.stdout, "columns", { configurable: true, value: 40 });
+    // Left to wrap, the title flex-shrinks the glyph column away entirely.
+    instance.rerender(
+      <TaskList
+        tasks={[
+          {
+            title: "Updating project spec file at '/a/very/long/absolute/path/agentcore.json'",
+            state: "done",
+            tail: [],
+          },
+        ]}
+      />,
+    );
+
+    const lines = (instance.lastFrame() ?? "").split("\n").filter((line) => line.trim());
+    expect(lines).toHaveLength(1);
+    expect(lines[0]).toStartWith("✓ Updating project spec file");
+    expect(lines[0]).toContain("…");
+    instance.unmount();
+  });
+
   test("truncates tail lines to the terminal width", () => {
     const instance = render(<></>);
     Object.defineProperty(instance.stdout, "columns", { configurable: true, value: 24 });

src/components/ui/task-list/TaskList.tsx

@@ -40,19 +40,23 @@ export const TaskList: React.FC<TaskListProps> = ({
   // `||`, not `??`: a pty can report 0 columns, which would truncate every
   // tail line to nothing. Match Ink's own layout fallback of 80.
   const columns = stdout?.columns || 80;
+  // One line per step: a title left to wrap flex-shrinks the 1-char glyph
+  // column to nothing, so the ✓/✕/spinner disappears. The glyph and its
+  // trailing space take 2 of the row's columns.
+  const title = (task: Task) => cliTruncate(task.title, Math.max(columns - 2, 3));
 
   return (
     <Box flexDirection="column">
       {tasks.map((task, index) => (
         <Box key={`${index}-${task.title}`} flexDirection="column">
           {task.state === "running" ? (
-            <Spinner label={task.title} theme={theme} />
+            <Spinner label={title(task)} theme={theme} />
           ) : (
             <Box>
               <Text color={task.state === "done" ? theme.colors.success : theme.colors.error}>
                 {task.state === "done" ? "✓" : "✕"}
               </Text>
-              <Text color={theme.colors.text}> {task.title}</Text>
+              <Text color={theme.colors.text}> {title(task)}</Text>
             </Box>
           )}
           {task.state !== "done" &&

src/core/project/manager.test.ts

@@ -279,6 +279,29 @@ describe("FsProjectManager.create", () => {
     ]);
   });
 
+  test("streams subprocess output as line-buffered output events", async () => {
+    await inTempDirectory();
+    const subject = new FsProjectManager({
+      logger: createSilentLogger(),
+      // The chunk boundary splits a line, so a chunk-per-event bridge would
+      // leak the fragments "vulnerabilit" / "ies".
+      runner: async (_command, { onOutput }) => {
+        onOutput?.("added 12 packages\nfound 0 vulnerabilit");
+        onOutput?.("ies\n");
+      },
+      checkTool: async () => {},
+      identity: new TestIdentityClient(),
+    });
+
+    const { events } = await runCreate(subject, {
+      name: "example",
+      scaffoldRuntimeInput: AGENT_PYTHON,
+    });
+
+    expect(events).toContainEqual({ type: "output", line: "added 12 packages" });
+    expect(events).toContainEqual({ type: "output", line: "found 0 vulnerabilities" });
+  });
+
   test("skipInstall skips npm install and uv sync", async () => {
     const directory = await inTempDirectory();
     const { manager: subject, commands } = manager();

src/handlers/project/create/index.ts

@@ -25,7 +25,8 @@ import {
   type HarnessModelProvider,
 } from "../../../projectSchemas/harness";
 import { InputValidationError } from "../../../errors";
-import { parseJsonFlag } from "../../utils";
+import { JsonRendererKey } from "../../../tui";
+import { parseJsonFlag, renderJsonError } from "../../utils";
 import { DEFAULT_HARNESS_MODEL } from "../add/harness";
 import type { CoreBedrockAgentImporter } from "../../../core/project/bedrockAgentImport";
 import { importScaffoldRuntimeInput, resolveImportBedrockAgentInput } from "../importBedrockAgent";
@@ -196,6 +197,7 @@ export const createCreateProjectHandler = (config: CreateProjectHandlerConfig) =
       flag("skip-git", "skip initializing a git repository", z.boolean().default(false)),
     ],
     handle: async (ctx, flags) => {
+      const jsonOutput = ctx.require(JsonKey);
       const name = flags["name"];
       if (name === undefined) {
         throw new InputValidationError("required option '--name <name>' not specified");
@@ -305,13 +307,20 @@ export const createCreateProjectHandler = (config: CreateProjectHandlerConfig) =
 
       // Same driver as build and deploy: a live step list in a TTY, and the previous plain
       // line-per-step output when stderr is not a TTY or --json wants no ANSI on it.
-      await runWithProgress(config.projectManager.create(createInput), {
-        io: config.io,
-        interactive: ctx.require(JsonKey) ? false : undefined,
-      });
+      try {
+        await runWithProgress(config.projectManager.create(createInput), {
+          io: config.io,
+          interactive: jsonOutput ? false : undefined,
+        });
+      } catch (error) {
+        if (jsonOutput) renderJsonError(ctx, error);
+        throw error;
+      }
 
-      config.io.stderr.write(`Created project '${name}' in ./${name}\n`);
+      const message = `Created project '${name}' in ./${name}`;
+      config.io.stderr.write(`${message}\n`);
       config.io.stderr.write(`To deploy it: cd ${name} && agentcore project deploy\n`);
+      if (jsonOutput) ctx.require(JsonRendererKey).renderJson({ message });
     },
   });
 

src/handlers/project/project.test.ts

@@ -387,6 +387,40 @@ describe("project create", () => {
     expect(io.stderr()).toContain("Syncing Python dependencies with uv");
     expect(io.stderr()).toContain("Initializing git repository");
     expect(io.stderr()).toContain("Created project 'MyAgent' in ./MyAgent");
+    expect(io.stdout()).toBe("");
+  });
+
+  test("renders the success message as JSON with --json", async () => {
+    await inTempDirectory();
+    const { io } = await run([
+      "create",
+      "--name",
+      "MyAgent",
+      "--skip-install",
+      "--skip-git",
+      "--json",
+    ]);
+
+    expect(JSON.parse(io.stdout())).toEqual({ message: "Created project 'MyAgent' in ./MyAgent" });
+  });
+
+  test("renders a create failure as JSON without changing the thrown error", async () => {
+    await inTempDirectory();
+    await run(["create", "--name", "MyAgent", "--skip-install", "--skip-git"]);
+
+    // The run helper builds io after routing, so drive the failing route with
+    // its own io to read what the command wrote before rejecting.
+    const io = testIO();
+    const root = createRootHandler(new TestCoreClient(), {
+      io: io.io,
+      globalConfigAccessor: new TestGlobalConfigAccessor(),
+      logger: createSilentLogger(),
+    });
+    const args = ["create", "--name", "MyAgent", "--skip-install", "--skip-git", "--json"];
+
+    await expect(root.route(["node", "agentcore", "project", ...args])).rejects.toThrow(/MyAgent/);
+
+    expect(JSON.parse(io.stdout())).toEqual({ error: expect.stringContaining("MyAgent") });
   });
 
   test("--skip-install and --skip-git run no commands", async () => {