diff --git a/tests/plugins/test_github_repo_filter.py b/tests/plugins/test_github_repo_filter.py
new file mode 100644
index 0000000..c5aa178
--- /dev/null
+++ b/tests/plugins/test_github_repo_filter.py
@@ -0,0 +1,97 @@
+"""Tests for GitHubRepoFilterPlugin lifecycle and configuration."""
+
+import pytest
+
+from mcp_zero.pipeline.registry import HookRegistry
+from mcp_zero.plugin import Plugin
+from mcp_zero.plugins.github_repo_filter import (
+    GitHubRepoFilterHook,
+    GitHubRepoFilterPlugin,
+)
+
+
+class TestGitHubRepoFilterPlugin:
+    def test_satisfies_plugin_protocol(self):
+        """isinstance check against Plugin protocol."""
+        plugin = GitHubRepoFilterPlugin()
+        assert isinstance(plugin, Plugin)
+
+    def test_name(self):
+        """Returns 'github-repo-filter'."""
+        assert GitHubRepoFilterPlugin().name == "github-repo-filter"
+
+    def test_configure_allowlist(self):
+        """Stores allowlist mode and repos."""
+        plugin = GitHubRepoFilterPlugin()
+        plugin.configure({"mode": "allowlist", "repos": ["org/repo-a", "org/repo-b"]})
+        assert plugin._mode == "allowlist"
+        assert plugin._repos == ["org/repo-a", "org/repo-b"]
+
+    def test_configure_blocklist(self):
+        """Stores blocklist mode and repos."""
+        plugin = GitHubRepoFilterPlugin()
+        plugin.configure({"mode": "blocklist", "repos": ["org/repo-x"]})
+        assert plugin._mode == "blocklist"
+        assert plugin._repos == ["org/repo-x"]
+
+    def test_configure_missing_mode_raises(self):
+        """ValueError when mode is missing."""
+        plugin = GitHubRepoFilterPlugin()
+        with pytest.raises(ValueError, match="'allowlist' or 'blocklist'"):
+            plugin.configure({"repos": ["org/repo"]})
+
+    def test_configure_invalid_mode_raises(self):
+        """ValueError when mode is not allowlist/blocklist."""
+        plugin = GitHubRepoFilterPlugin()
+        with pytest.raises(ValueError, match="'allowlist' or 'blocklist'"):
+            plugin.configure({"mode": "denylist", "repos": ["org/repo"]})
+
+    def test_configure_empty_repos_raises(self):
+        """ValueError when repos list is empty."""
+        plugin = GitHubRepoFilterPlugin()
+        with pytest.raises(ValueError, match="non-empty 'repos' list"):
+            plugin.configure({"mode": "allowlist", "repos": []})
+
+    def test_configure_missing_repos_raises(self):
+        """ValueError when repos key is missing."""
+        plugin = GitHubRepoFilterPlugin()
+        with pytest.raises(ValueError, match="non-empty 'repos' list"):
+            plugin.configure({"mode": "allowlist"})
+
+    def test_configure_invalid_repo_format_raises(self):
+        """ValueError for entries without '/'."""
+        plugin = GitHubRepoFilterPlugin()
+        with pytest.raises(ValueError, match="containing '/'"):
+            plugin.configure({"mode": "allowlist", "repos": ["noslash"]})
+
+    def test_configure_custom_priority(self):
+        """Overrides default priority of 55."""
+        plugin = GitHubRepoFilterPlugin()
+        plugin.configure({"mode": "allowlist", "repos": ["org/repo"], "priority": 30})
+        assert plugin._priority == 30
+
+    def test_configure_servers_list(self):
+        """Stores server filter list."""
+        plugin = GitHubRepoFilterPlugin()
+        plugin.configure(
+            {
+                "mode": "allowlist",
+                "repos": ["org/repo"],
+                "servers": ["github-server", "gh-enterprise"],
+            }
+        )
+        assert plugin._servers == ["github-server", "gh-enterprise"]
+
+    def test_register_adds_hook_to_registry(self):
+        """Verifies hook appears in registry after build()."""
+        plugin = GitHubRepoFilterPlugin()
+        plugin.configure({"mode": "allowlist", "repos": ["org/repo"]})
+        registry = HookRegistry()
+        plugin.register(registry)
+        registry.build()
+        hooks = registry.get_hooks()
+        assert len(hooks) == 1
+        assert isinstance(hooks[0], GitHubRepoFilterHook)
+        # Verify config was passed through
+        assert hooks[0]._mode == "allowlist"
+        assert hooks[0]._repos == ["org/repo"]