fix(tools): use numeric issue IDs after lookup

docs/contributing/api-patterns.md

@@ -63,6 +63,11 @@ await api.issues.update({
 });
 ```
 
+### Resolved Issue IDs
+
+Use `String(issue.id)` for API requests after resolving an issue. Short IDs can
+fail to resolve for legacy mixed-case project slugs; keep them for display.
+
 ### Multi-Region Support
 
 Sentry uses region-specific URLs:

packages/mcp-core/src/tools/catalog/get-issue-details.numeric-id.test.ts

@@ -0,0 +1,95 @@
+import {
+  autofixStateFixture,
+  eventsFixture,
+  issueFixture,
+  mswServer,
+} from "@sentry/mcp-server-mocks";
+import { http, HttpResponse } from "msw";
+import { describe, expect, it } from "vitest";
+import getIssueDetails from "./get-issue-details";
+import getSentryResource from "./get-sentry-resource";
+
+const organizationSlug = "sentry-mcp-evals";
+const issueId = String(issueFixture.id);
+const eventId = eventsFixture.id;
+const issueUrl = `https://${organizationSlug}.sentry.io/issues/${issueId}/`;
+const context = {
+  constraints: { organizationSlug: undefined },
+  accessToken: "access-token",
+  userId: "1",
+};
+
+describe("issue details with an unresolvable short ID", () => {
+  it.each([
+    {
+      name: "numeric issue ID",
+      call: () =>
+        getIssueDetails.handler(
+          { organizationSlug, issueId, regionUrl: null },
+          context,
+        ),
+    },
+    {
+      name: "issue URL",
+      call: () =>
+        getIssueDetails.handler({ issueUrl, regionUrl: null }, context),
+    },
+    {
+      name: "numeric issue ID and explicit event ID",
+      call: () =>
+        getIssueDetails.handler(
+          { organizationSlug, issueId, eventId, regionUrl: null },
+          context,
+        ),
+    },
+    {
+      name: "event ID resolved through issue search",
+      call: () =>
+        getIssueDetails.handler(
+          { organizationSlug, eventId, regionUrl: null },
+          context,
+        ),
+    },
+    {
+      name: "resource issue URL",
+      call: () => getSentryResource.handler({ url: issueUrl }, context),
+    },
+    {
+      name: "resource event URL",
+      call: () =>
+        getSentryResource.handler(
+          { url: `${issueUrl}events/${eventId}/` },
+          context,
+        ),
+    },
+  ])("loads $name and enrichment by numeric ID", async ({ call }) => {
+    const base = `https://sentry.io/api/0/organizations/${organizationSlug}`;
+    mswServer.use(
+      http.get(`${base}/issues/`, () => HttpResponse.json([issueFixture])),
+      http.get(`${base}/issues/${issueFixture.shortId}/*`, () =>
+        HttpResponse.json({ detail: "Not found" }, { status: 404 }),
+      ),
+      http.get(`${base}/issues/${issueId}/autofix/`, () =>
+        HttpResponse.json(autofixStateFixture),
+      ),
+      http.get(`${base}/issues/${issueId}/external-issues/`, () =>
+        HttpResponse.json([
+          {
+            id: "123",
+            issueId,
+            serviceType: "github",
+            displayName: "example/app#123",
+            webUrl: "https://github.com/example/app/issues/123",
+          },
+        ]),
+      ),
+    );
+
+    const result = await call();
+
+    expect(result).toContain(`Issue ${issueFixture.shortId}`);
+    expect(result).toContain(eventsFixture.id);
+    expect(result).toContain("## Seer Analysis");
+    expect(result).toContain("**example/app#123** (github)");
+  });
+});