fix: correct threadId extraction in SuperhumanDraftProvider (closes #14)

The userdata.getThreads API returns threadId at the top level
(threadItem.id), not inside the thread object (threadItem.thread.id).
This caused threadId to be undefined, producing invalid API paths
like threads/undefined/messages/... which returned HTTP 400.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: claude

package.json

@@ -1,6 +1,6 @@
 {
   "name": "superhuman-cli",
-  "version": "0.13.1",
+  "version": "0.13.2",
   "module": "src/index.ts",
   "type": "module",
   "private": true,

src/__tests__/draft-service.test.ts

@@ -6,6 +6,7 @@
 
 import { describe, it, expect } from "bun:test";
 import { DraftService, type IDraftProvider, type Draft } from "../services/draft-service";
+import { SuperhumanDraftProvider } from "../providers/superhuman-draft-provider";
 
 // Mock provider for testing
 class MockProvider implements IDraftProvider {
@@ -118,3 +119,78 @@ describe("DraftService", () => {
     expect(() => new DraftService(notAnArray)).toThrow(TypeError);
   });
 });
+
+describe("SuperhumanDraftProvider", () => {
+  it("should correctly extract threadId from getThreads response", () => {
+    // Regression test: threadId lives at threadItem.id (top level), NOT threadItem.thread.id
+    // The userdata.getThreads API returns: { id: "draft00...", thread: { historyId: ..., messages: {...} } }
+    const mockThreadList = [
+      {
+        id: "draft00bc30654cd5d898",
+        thread: {
+          historyId: 49480,
+          messages: {
+            "draft00bc30654cd5d898": {
+              draft: {
+                id: "draft00bc30654cd5d898",
+                subject: "Test Draft",
+                to: ["recipient@example.com"],
+                from: "sender@example.com",
+                snippet: "Draft body preview",
+                date: "2026-02-26T10:00:00Z",
+              },
+            },
+          },
+        },
+      },
+    ];
+
+    // Access the private parseThreadList method via prototype
+    const provider = new SuperhumanDraftProvider({
+      superhumanToken: { token: "fake" },
+    } as any);
+
+    // Call parseThreadList using bracket notation to access private method
+    const drafts = (provider as any).parseThreadList(mockThreadList);
+
+    expect(drafts).toHaveLength(1);
+    expect(drafts[0].threadId).toBe("draft00bc30654cd5d898");
+    expect(drafts[0].threadId).not.toBeUndefined();
+    expect(drafts[0].id).toBe("draft00bc30654cd5d898");
+    expect(drafts[0].subject).toBe("Test Draft");
+    expect(drafts[0].source).toBe("native");
+  });
+
+  it("should handle thread items with no id gracefully", () => {
+    // Ensure undefined threadId is captured (rather than crashing)
+    const mockThreadList = [
+      {
+        // id is missing at top level
+        thread: {
+          historyId: 12345,
+          messages: {
+            "draft001": {
+              draft: {
+                id: "draft001",
+                subject: "No Thread ID",
+                to: [],
+                from: "test@example.com",
+                snippet: "",
+                date: "2026-02-26T10:00:00Z",
+              },
+            },
+          },
+        },
+      },
+    ];
+
+    const provider = new SuperhumanDraftProvider({
+      superhumanToken: { token: "fake" },
+    } as any);
+
+    const drafts = (provider as any).parseThreadList(mockThreadList);
+
+    expect(drafts).toHaveLength(1);
+    expect(drafts[0].threadId).toBeUndefined();
+  });
+});

src/providers/superhuman-draft-provider.ts

@@ -32,8 +32,9 @@ interface SuperhumanMessage {
 }
 
 interface SuperhumanThread {
+  id: string; // threadId is at the top level, NOT inside thread
   thread: {
-    id: string;
+    historyId?: number;
     messages: Record<string, SuperhumanMessage>;
   };
 }
@@ -188,7 +189,7 @@ export class SuperhumanDraftProvider implements IDraftProvider {
     const drafts: Draft[] = [];
 
     for (const threadItem of threadList) {
-      const threadId = threadItem.thread?.id;
+      const threadId = threadItem.id;
       const messages = threadItem.thread?.messages || {};
 
       for (const [messageId, message] of Object.entries(messages)) {