diff --git a/app/(dashboard)/dashboard/pull-request.test.tsx b/app/(dashboard)/dashboard/pull-request.test.tsx
index 06ed0e6f..bf366543 100644
--- a/app/(dashboard)/dashboard/pull-request.test.tsx
+++ b/app/(dashboard)/dashboard/pull-request.test.tsx
@@ -8,6 +8,7 @@ import { generateTestsResponseSchema } from "@/app/api/generate-tests/schema";
 vi.mock('@/lib/github', () => ({
   getPullRequestInfo: vi.fn(),
   commitChangesToPullRequest: vi.fn(),
+  getFailingTests: vi.fn(),
 }));
 
 vi.mock('@/hooks/use-toast', () => ({
@@ -56,7 +57,7 @@ describe('PullRequestItem', () => {
     expect(screen.getByText('Build: success')).toBeInTheDocument();
   });
 
-  it('handles "Write new tests" button click', async () => {
+  it('handles "Write new tests" button click for successful build', async () => {
     const { getPullRequestInfo } = await import('@/lib/github');
     vi.mocked(getPullRequestInfo).mockResolvedValue({
       diff: 'mock diff',
@@ -68,7 +69,7 @@ describe('PullRequestItem', () => {
       json: () => Promise.resolve([{ name: 'generated_test.ts', content: 'generated content' }]),
     } as Response);
 
-    render(<PullRequestItem pullRequest={mockPullRequest} />);
+    render(<PullRequestItem pullRequest={{ ...mockPullRequest, buildStatus: 'success' }} />);
     const writeTestsButton = screen.getByText('Write new tests');
     fireEvent.click(writeTestsButton);
 
@@ -82,17 +83,23 @@ describe('PullRequestItem', () => {
     });
   });
 
-  it('handles "Update tests to fix" button click', async () => {
+  it('handles "Update tests to fix" button click for failed build', async () => {
     const failedPR = { ...mockPullRequest, buildStatus: 'failure' };
-    const { getPullRequestInfo } = await import('@/lib/github');
+    const { getPullRequestInfo, getFailingTests } = await import('@/lib/github');
     vi.mocked(getPullRequestInfo).mockResolvedValue({
       diff: 'mock diff',
-      testFiles: [{ name: 'test.ts', content: 'test content' }],
+      testFiles: [
+        { name: 'test1.ts', content: 'test content 1' },
+        { name: 'test2.ts', content: 'test content 2' },
+      ],
     });
+    vi.mocked(getFailingTests).mockResolvedValue([
+      { name: 'test1.ts', content: 'failing test content' },
+    ]);
 
     vi.mocked(global.fetch).mockResolvedValue({
       ok: true,
-      json: () => Promise.resolve([{ name: 'fixed_test.ts', content: 'fixed content' }]),
+      json: () => Promise.resolve([{ name: 'test1.ts', content: 'fixed content' }]),
     } as Response);
 
     render(<PullRequestItem pullRequest={failedPR} />);
@@ -104,7 +111,8 @@ describe('PullRequestItem', () => {
     });
 
     await waitFor(() => {
-      expect(screen.getByText('fixed_test.ts')).toBeInTheDocument();
+      expect(screen.getByText('test1.ts')).toBeInTheDocument();
+      expect(screen.queryByText('test2.ts')).not.toBeInTheDocument();
       expect(screen.getByTestId('react-diff-viewer')).toBeInTheDocument();
     });
   });
@@ -120,10 +128,6 @@ describe('PullRequestItem', () => {
       ok: false,
     } as Response);
 
-    const { useToast } = await import('@/hooks/use-toast');
-    const mockToast = vi.fn();
-    vi.mocked(useToast).mockReturnValue({ toast: mockToast });
-
     render(<PullRequestItem pullRequest={mockPullRequest} />);
     const writeTestsButton = screen.getByText('Write new tests');
     fireEvent.click(writeTestsButton);
@@ -259,4 +263,25 @@ describe('PullRequestItem', () => {
       }));
     });
   });
+
+  it('displays pending build status', () => {
+    const pendingPR = { ...mockPullRequest, buildStatus: 'pending' };
+    render(<PullRequestItem pullRequest={pendingPR} />);
+    expect(screen.getByText('Build: pending')).toBeInTheDocument();
+  });
+
+  it('disables buttons when loading', async () => {
+    vi.mocked(global.fetch).mockResolvedValue({
+      ok: true,
+      json: () => new Promise(resolve => setTimeout(() => resolve([]), 100)),
+    } as Response);
+
+    render(<PullRequestItem pullRequest={mockPullRequest} />);
+    const writeTestsButton = screen.getByText('Write new tests');
+    fireEvent.click(writeTestsButton);
+
+    await waitFor(() => {
+      expect(writeTestsButton).toBeDisabled();
+    });
+  });
 });
\ No newline at end of file
diff --git a/app/(dashboard)/dashboard/pull-request.tsx b/app/(dashboard)/dashboard/pull-request.tsx
index 55a9591d..d46e2463 100644
--- a/app/(dashboard)/dashboard/pull-request.tsx
+++ b/app/(dashboard)/dashboard/pull-request.tsx
@@ -18,7 +18,7 @@ import dynamic from "next/dynamic";
 import { PullRequest, TestFile } from "./types";
 import { generateTestsResponseSchema } from "@/app/api/generate-tests/schema";
 import { useToast } from "@/hooks/use-toast";
-import { commitChangesToPullRequest, getPullRequestInfo } from "@/lib/github";
+import { commitChangesToPullRequest, getPullRequestInfo, getFailingTests } from "@/lib/github";
 
 const ReactDiffViewer = dynamic(() => import("react-diff-viewer"), {
   ssr: false,
@@ -53,6 +53,19 @@ export function PullRequestItem({ pullRequest }: PullRequestItemProps) {
         pr.number
       );
 
+      let testFilesToUpdate = oldTestFiles;
+
+      if (mode === "update") {
+        const failingTests = await getFailingTests(
+          pr.repository.owner.login,
+          pr.repository.name,
+          pr.number
+        );
+        testFilesToUpdate = oldTestFiles.filter(file => 
+          failingTests.some(failingFile => failingFile.name === file.name)
+        );
+      }
+
       const response = await fetch("/api/generate-tests", {
         method: "POST",
         headers: {
@@ -62,7 +75,7 @@ export function PullRequestItem({ pullRequest }: PullRequestItemProps) {
           mode,
           pr_id: pr.id,
           pr_diff: diff,
-          test_files: oldTestFiles,
+          test_files: testFilesToUpdate,
         }),
       });
 
diff --git a/app/api/generate-tests/route.ts b/app/api/generate-tests/route.ts
index 93510fd6..ee01f659 100644
--- a/app/api/generate-tests/route.ts
+++ b/app/api/generate-tests/route.ts
@@ -12,7 +12,7 @@ export async function POST(req: Request) {
   const prompt = `You are an expert software engineer. ${
     mode === "write"
       ? "Write entirely new tests and update relevant existing tests in order to reflect the added/edited/removed functionality."
-      : "Update existing test files in order to get the PR build back to passing. Make updates to tests solely, do not add or remove tests."
+      : "Update the provided failing test files in order to get the PR build back to passing. Make updates to tests solely, do not add or remove tests."
   }
 
   PR Diff:
@@ -20,7 +20,7 @@ export async function POST(req: Request) {
   ${pr_diff}
   </PR Diff>
 
-  Existing test files:
+  ${mode === "update" ? "Failing test files:" : "Existing test files:"}
   <Test Files>
   ${test_files
     .map((file) => `${file.name}\n${file.content ? `: ${file.content}` : ""}`)
diff --git a/lib/github.ts b/lib/github.ts
index 069ec40f..13be9e64 100644
--- a/lib/github.ts
+++ b/lib/github.ts
@@ -270,3 +270,59 @@ export async function getPullRequestInfo(
     throw new Error("Failed to fetch PR info");
   }
 }
+
+export async function getFailingTests(
+  owner: string,
+  repo: string,
+  pullNumber: number
+): Promise<TestFile[]> {
+  const octokit = await getOctokit();
+
+  try {
+    const { data: checkRuns } = await octokit.checks.listForRef({
+      owner,
+      repo,
+      ref: `refs/pull/${pullNumber}/head`,
+      status: 'completed',
+      filter: 'latest',
+    });
+
+    const failedChecks = checkRuns.check_runs.filter(
+      (run) => run.conclusion === 'failure'
+    );
+
+    const failingTestFiles: TestFile[] = [];
+    for (const check of failedChecks) {
+      if (check.output.annotations_count > 0) {
+        const { data: annotations } = await octokit.checks.listAnnotations({
+          owner,
+          repo,
+          check_run_id: check.id,
+        });
+
+        for (const annotation of annotations) {
+          if (annotation.path.includes('test') || annotation.path.includes('spec')) {
+            const { data: fileContent } = await octokit.repos.getContent({
+              owner,
+              repo,
+              path: annotation.path,
+              ref: `refs/pull/${pullNumber}/head`,
+            });
+
+            if ('content' in fileContent) {
+              failingTestFiles.push({
+                name: annotation.path,
+                content: Buffer.from(fileContent.content, 'base64').toString('utf-8'),
+              });
+            }
+          }
+        }
+      }
+    }
+
+    return failingTestFiles;
+  } catch (error) {
+    console.error('Error fetching failing tests:', error);
+    throw error;
+  }
+}