fix(project): disambiguate 404 errors from create endpoint

The /teams/{org}/{team}/projects/ endpoint returns 404 for both a bad
org and a bad team. Previously we always blamed the team, which was
misleading when --team was explicit and the org was auto-detected wrong.

Now on 404 we call listTeams(orgSlug) to check:
- If it succeeds → team is wrong, show available teams
- If it fails → org is wrong, show user's actual organizations

Only adds an API call on the error path, never on the happy path.

Author: betegon

src/commands/project/create.ts

@@ -6,7 +6,12 @@
  */
 
 import type { SentryContext } from "../../context.js";
-import { createProject, tryGetPrimaryDsn } from "../../lib/api-client.js";
+import {
+  createProject,
+  listOrganizations,
+  listTeams,
+  tryGetPrimaryDsn,
+} from "../../lib/api-client.js";
 import { parseOrgPrefixedArg } from "../../lib/arg-parsing.js";
 import { buildCommand } from "../../lib/command.js";
 import { ApiError, CliError, ContextError } from "../../lib/errors.js";
@@ -81,6 +86,55 @@ function buildPlatformError(nameArg: string, platform?: string): string {
   );
 }
 
+/**
+ * Disambiguate a 404 from the create project endpoint.
+ *
+ * The `/teams/{org}/{team}/projects/` endpoint returns 404 for both
+ * a bad org and a bad team. This helper calls `listTeams` to determine
+ * which is wrong, then throws an actionable error.
+ *
+ * Only called on the error path — no cost to the happy path.
+ */
+async function handleCreateProject404(
+  orgSlug: string,
+  teamSlug: string,
+  name: string,
+  platform: string
+): Promise<never> {
+  // If listTeams succeeds, the org is valid and the team is wrong
+  const teams = await listTeams(orgSlug).catch(() => null);
+
+  if (teams !== null) {
+    if (teams.length > 0) {
+      const teamList = teams.map((t) => `  ${t.slug}`).join("\n");
+      throw new CliError(
+        `Team '${teamSlug}' not found in ${orgSlug}.\n\n` +
+          `Available teams:\n\n${teamList}\n\n` +
+          "Try:\n" +
+          `  sentry project create ${orgSlug}/${name} ${platform} --team <team-slug>`
+      );
+    }
+    throw new CliError(
+      `No teams found in ${orgSlug}.\n\n` +
+        "Create a team first, then try again."
+    );
+  }
+
+  // listTeams also failed — org is likely wrong
+  let orgHint = `Specify org explicitly: ${USAGE_HINT}`;
+  try {
+    const orgs = await listOrganizations();
+    if (orgs.length > 0) {
+      const orgList = orgs.map((o) => `  ${o.slug}`).join("\n");
+      orgHint = `Your organizations:\n\n${orgList}`;
+    }
+  } catch {
+    // Best-effort — if this also fails, use the generic hint
+  }
+
+  throw new CliError(`Organization '${orgSlug}' not found.\n\n${orgHint}`);
+}
+
 /**
  * Create a project with user-friendly error handling.
  * Wraps API errors with actionable messages instead of raw HTTP status codes.
@@ -105,11 +159,7 @@ async function createProjectWithErrors(
         throw new CliError(buildPlatformError(`${orgSlug}/${name}`, platform));
       }
       if (error.status === 404) {
-        throw new CliError(
-          `Team '${teamSlug}' not found in ${orgSlug}.\n\n` +
-            "Check the team slug and try again:\n" +
-            `  sentry project create ${orgSlug}/${name} ${platform} --team <team-slug>`
-        );
+        await handleCreateProject404(orgSlug, teamSlug, name, platform);
       }
       throw new CliError(
         `Failed to create project '${name}' in ${orgSlug}.\n\n` +

test/commands/project/create.test.ts

@@ -206,7 +206,7 @@ describe("project create", () => {
     expect(err.message).toContain("sentry project view");
   });
 
-  test("handles 404 from createProject as team-not-found", async () => {
+  test("handles 404 from createProject as team-not-found with available teams", async () => {
     createProjectSpy.mockRejectedValue(
       new ApiError("API request failed: 404 Not Found", 404)
     );
@@ -219,9 +219,32 @@ describe("project create", () => {
       .catch((e: Error) => e);
     expect(err).toBeInstanceOf(CliError);
     expect(err.message).toContain("Team 'engineering' not found");
+    expect(err.message).toContain("Available teams:");
+    expect(err.message).toContain("engineering");
     expect(err.message).toContain("--team <team-slug>");
   });
 
+  test("handles 404 from createProject with bad org — shows user's orgs", async () => {
+    createProjectSpy.mockRejectedValue(
+      new ApiError("API request failed: 404 Not Found", 404)
+    );
+    // listTeams also fails → org is bad
+    listTeamsSpy.mockRejectedValue(
+      new ApiError("API request failed: 404 Not Found", 404)
+    );
+
+    const { context } = createMockContext();
+    const func = await createCommand.loader();
+
+    const err = await func
+      .call(context, { json: false, team: "backend" }, "my-app", "node")
+      .catch((e: Error) => e);
+    expect(err).toBeInstanceOf(CliError);
+    expect(err.message).toContain("Organization 'acme-corp' not found");
+    expect(err.message).toContain("Your organizations");
+    expect(err.message).toContain("other-org");
+  });
+
   test("handles 400 invalid platform with platform list", async () => {
     createProjectSpy.mockRejectedValue(
       new ApiError(