diff --git a/backend/app/services/agents/tests/__pycache__/test_code_audit_agent.cpython-313-pytest-8.4.2.pyc b/backend/app/services/agents/tests/__pycache__/test_code_audit_agent.cpython-313-pytest-8.4.2.pyc
index 434714e..b481344 100644
Binary files a/backend/app/services/agents/tests/__pycache__/test_code_audit_agent.cpython-313-pytest-8.4.2.pyc and b/backend/app/services/agents/tests/__pycache__/test_code_audit_agent.cpython-313-pytest-8.4.2.pyc differ
diff --git a/backend/app/services/agents/tests/test_code_audit_agent.py b/backend/app/services/agents/tests/test_code_audit_agent.py
index 83e8d27..c033b04 100644
--- a/backend/app/services/agents/tests/test_code_audit_agent.py
+++ b/backend/app/services/agents/tests/test_code_audit_agent.py
@@ -1,9 +1,10 @@
 import pytest
 import pytest_asyncio
 import respx
-from httpx import Response
+from httpx import Response, Request, HTTPStatusError, RequestError
 from backend.app.services.agents.code_audit_agent import CodeAuditAgent, CodeMetrics, AuditSummary, CodeAuditResult
 
+
 @pytest_asyncio.fixture
 async def code_audit_agent():
     async with CodeAuditAgent() as agent:
@@ -22,7 +23,6 @@ async def test_fetch_github_repo_metrics(code_audit_agent):
         respx.get(f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/contributors?per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/contributors?per_page=1&page=5>; rel="last"'}, json=[]))
         # Mock latest release
         respx.get(f"https://api.github.com/repos/{owner}/{repo}/releases/latest").mock(return_value=Response(200, json={'tag_name': 'v1.0.0'}))
-        # Mock issues count using GitHub Search API
         respx.get(f"https://api.github.com/search/issues?q=repo%3A{owner}%2F{repo}%2Btype%3Aissue&per_page=1").mock(return_value=Response(200, json={'total_count': 20}))
         # Mock pull requests count
         respx.get(f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=15>; rel="last"'}, json=[]))
@@ -102,11 +102,11 @@ async def test_audit_codebase(code_audit_agent):
 
     with respx.mock:
         # Mock GitHub API calls for fetch_repo_metrics
-        respx.get(f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/commits?per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/commits?per_page=1&page=10>; rel="last"'}))
-        respx.get(f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/contributors?per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/contributors?per_page=1&page=5>; rel="last"'}))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/commits?per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/commits?per_page=1&page=10>; rel="last"'}, json=[]))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/contributors?per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/contributors?per_page=1&page=5>; rel="last"'}, json=[]))
         respx.get(f"https://api.github.com/repos/{owner}/{repo}/releases/latest").mock(return_value=Response(200, json={'tag_name': 'v1.0.0'}))
         respx.get(f"https://api.github.com/search/issues?q=repo%3A{owner}%2F{repo}%2Btype%3Aissue&per_page=1").mock(return_value=Response(200, json={'total_count': 20}))
-        respx.get(f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=15>; rel="last"'}))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1").mock(return_value=Response(200, headers={'link': '<https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=2>; rel="next", <https://api.github.com/repositories/1296269/pulls?state=all&per_page=1&page=15>; rel="last"'}, json=[]))
 
         result = await code_audit_agent.audit_codebase(repo_url, project_name)
 
@@ -115,3 +115,128 @@ async def test_audit_codebase(code_audit_agent):
         assert len(result.audit_summaries) == 2
         assert project_name in result.audit_summaries[0].report_title
 
+@pytest.mark.asyncio
+async def test_fetch_github_repo_metrics_http_error(code_audit_agent):
+    repo_url = "https://github.com/nonexistent/repo"
+    owner = "nonexistent"
+    repo = "repo"
+
+    with respx.mock:
+        # Mock all GitHub API calls to return 404 Not Found
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/releases/latest").mock(return_value=Response(404))
+        respx.get(f"https://api.github.com/search/issues?q=repo%3A{owner}%2F{repo}%2Btype%3Aissue&per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1").mock(return_value=Response(404))
+
+        metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+        assert metrics.repo_url == repo_url
+        assert metrics.commits_count == 0
+        assert metrics.contributors_count == 0
+        assert metrics.latest_release == "N/A"
+        assert metrics.issues_count == 0
+        assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_github_repo_metrics_network_error(code_audit_agent):
+    repo_url = "https://github.com/owner/repo"
+    owner = "owner"
+    repo = "repo"
+
+    with respx.mock:
+        # Mock all GitHub API calls to raise a RequestError
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://api.github.com/repos/{owner}/{repo}/commits?per_page=1")))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://api.github.com/repos/{owner}/{repo}/contributors?per_page=1")))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/releases/latest").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://api.github.com/repos/{owner}/{repo}/releases/latest")))
+        respx.get(f"https://api.github.com/search/issues?q=repo%3A{owner}%2F{repo}%2Btype%3Aissue&per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://api.github.com/search/issues?q=repo%3A{owner}%2F{repo}%2Btype%3Aissue&per_page=1")))
+        respx.get(f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://api.github.com/repos/{owner}/{repo}/pulls?state=all&per_page=1")))
+
+        metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+        assert metrics.repo_url == repo_url
+        assert metrics.commits_count == 0
+        assert metrics.contributors_count == 0
+        assert metrics.latest_release == "N/A"
+        assert metrics.issues_count == 0
+        assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_gitlab_repo_metrics_http_error(code_audit_agent):
+    repo_url = "https://gitlab.com/nonexistent/repo"
+    project_id = "nonexistent%2Frepo"
+
+    with respx.mock:
+        # Mock all GitLab API calls to return 404 Not Found
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/commits?per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/contributors?per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/tags?per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/issues?scope=all&per_page=1").mock(return_value=Response(404))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/merge_requests?scope=all&per_page=1").mock(return_value=Response(404))
+
+        metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+        assert metrics.repo_url == repo_url
+        assert metrics.commits_count == 0
+        assert metrics.contributors_count == 0
+        assert metrics.latest_release == "N/A"
+        assert metrics.issues_count == 0
+        assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_gitlab_repo_metrics_network_error(code_audit_agent):
+    repo_url = "https://gitlab.com/group/project"
+    project_id = "group%2Fproject"
+
+    with respx.mock:
+        # Mock all GitLab API calls to raise a RequestError
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/commits?per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://gitlab.com/api/v4/projects/{project_id}/repository/commits?per_page=1")))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/contributors?per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://gitlab.com/api/v4/projects/{project_id}/repository/contributors?per_page=1")))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/repository/tags?per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://gitlab.com/api/v4/projects/{project_id}/repository/tags?per_page=1")))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/issues?scope=all&per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://gitlab.com/api/v4/projects/{project_id}/issues?scope=all&per_page=1")))
+        respx.get(f"https://gitlab.com/api/v4/projects/{project_id}/merge_requests?scope=all&per_page=1").mock(side_effect=RequestError("Network error", request=Request("GET", f"https://gitlab.com/api/v4/projects/{project_id}/merge_requests?scope=all&per_page=1")))
+
+        metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+        assert metrics.repo_url == repo_url
+        assert metrics.commits_count == 0
+        assert metrics.contributors_count == 0
+        assert metrics.latest_release == "N/A"
+        assert metrics.issues_count == 0
+        assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_repo_metrics_unsupported_url(code_audit_agent):
+    repo_url = "https://bitbucket.org/some/repo"
+    metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+    assert metrics.repo_url == repo_url
+    assert metrics.commits_count == 0
+    assert metrics.contributors_count == 0
+    assert metrics.latest_release == "N/A"
+    assert metrics.issues_count == 0
+    assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_repo_metrics_invalid_github_url_format(code_audit_agent):
+    repo_url = "https://github.com/owner_only"
+    metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+    assert metrics.repo_url == repo_url
+    assert metrics.commits_count == 0
+    assert metrics.contributors_count == 0
+    assert metrics.latest_release == "N/A"
+    assert metrics.issues_count == 0
+    assert metrics.pull_requests_count == 0
+
+@pytest.mark.asyncio
+async def test_fetch_repo_metrics_invalid_gitlab_url_format(code_audit_agent):
+    repo_url = "https://gitlab.com/group_only"
+    metrics = await code_audit_agent.fetch_repo_metrics(repo_url)
+
+    assert metrics.repo_url == repo_url
+    assert metrics.commits_count == 0
+    assert metrics.contributors_count == 0
+    assert metrics.latest_release == "N/A"
+    assert metrics.issues_count == 0
+    assert metrics.pull_requests_count == 0
\ No newline at end of file