fix: smarter fallback team selection for scope inference

packages/vercel-sandbox/src/auth/infer-scope.test.ts

@@ -28,16 +28,24 @@ async function getTempDir(): Promise<string> {
 }
 
 describe("selectTeam", () => {
-  test("returns the first team", async () => {
+  test("returns defaultTeamId when set", async () => {
     fetchApiMock.mockResolvedValue({
-      teams: [{ slug: "one" }, { slug: "two" }],
+      user: { defaultTeamId: "team_abc123", username: "my-user" },
     });
     const team = await selectTeam("token");
     expect(fetchApiMock).toHaveBeenCalledWith({
-      endpoint: "/v2/teams?limit=1",
+      endpoint: "/v2/user",
       token: "token",
     });
-    expect(team).toBe("one");
+    expect(team).toBe("team_abc123");
+  });
+
+  test("falls back to username when defaultTeamId is null", async () => {
+    fetchApiMock.mockResolvedValue({
+      user: { defaultTeamId: null, username: "my-user" },
+    });
+    const team = await selectTeam("token");
+    expect(team).toBe("my-user");
   });
 });
 
@@ -95,18 +103,18 @@ describe("inferScope", () => {
     });
   });
 
-  test("infers the team", async () => {
+  test("infers the team from the user's defaultTeamId", async () => {
     fetchApiMock.mockImplementation(async ({ endpoint }) => {
-      if (endpoint === "/v2/teams?limit=1") {
-        return { teams: [{ slug: "inferred-team" }] };
+      if (endpoint === "/v2/user") {
+        return { user: { defaultTeamId: "team_default", username: "my-user" } };
       }
       return {};
     });
     const scope = await inferScope({ token: "token" });
     expect(scope).toEqual({
       created: false,
       projectId: "vercel-sandbox-default-project",
-      teamId: "inferred-team",
+      teamId: "team_default",
     });
   });
 

packages/vercel-sandbox/src/auth/project.ts

@@ -3,14 +3,11 @@ import { fetchApi } from "./api.js";
 import { NotOk } from "./error.js";
 import { readLinkedProject } from "./linked-project.js";
 
-const TeamsSchema = z.object({
-  teams: z
-    .array(
-      z.object({
-        slug: z.string(),
-      }),
-    )
-    .min(1, `No teams found. Please create a team first.`),
+const UserSchema = z.object({
+  user: z.object({
+    defaultTeamId: z.string().nullable(),
+    username: z.string(),
+  }),
 });
 
 const DEFAULT_PROJECT_NAME = "vercel-sandbox-default-project";
@@ -21,16 +18,17 @@ const DEFAULT_PROJECT_NAME = "vercel-sandbox-default-project";
  * First checks for a locally linked project in `.vercel/project.json`.
  * If found, uses the `projectId` and `orgId` from there.
  *
- * Otherwise, if `teamId` is not provided, selects the first available team for the account.
- * Ensures a default project exists within the team, creating it if necessary.
+ * Otherwise, if `teamId` is not provided, falls back to the authenticated user's
+ * default team (`defaultTeamId`), or their personal team (username) if no default
+ * is configured. Ensures a default project exists within the team, creating it if necessary.
  *
  * @param opts.token - Vercel API authentication token.
- * @param opts.teamId - Optional team slug. If omitted, the first team is selected.
+ * @param opts.teamId - Optional team slug. If omitted, the user's default team is used.
  * @param opts.cwd - Optional directory to search for `.vercel/project.json`. Defaults to `process.cwd()`.
  * @returns The resolved scope with `projectId`, `teamId`, and whether the project was `created`.
  *
  * @throws {NotOk} If the API returns an error other than 404 when checking the project.
- * @throws {ZodError} If no teams exist for the account.
+ * @throws {ZodError} If the user API response is missing a username.
  *
  * @example
  * ```ts
@@ -76,17 +74,18 @@ export async function inferScope(opts: {
 }
 
 /**
- * Selects a team for the current token by querying the Teams API and
- * returning the slug of the first team in the result set.
+ * Falls back to the authenticated user's default team by fetching
+ * their profile from the `/v2/user` endpoint. Uses `defaultTeamId`
+ * if set, otherwise falls back to the user's personal team (username).
  *
  * @param token - Authentication token used to call the Vercel API.
- * @returns A promise that resolves to the first team's slug.
+ * @returns A promise that resolves to the user's default team ID or username.
  */
 export async function selectTeam(token: string) {
   const {
-    teams: [team],
-  } = await fetchApi({ token, endpoint: "/v2/teams?limit=1" }).then(
-    TeamsSchema.parse,
+    user,
+  } = await fetchApi({ token, endpoint: "/v2/user" }).then(
+    UserSchema.parse,
   );
-  return team.slug;
+  return user.defaultTeamId ?? user.username;
 }