Add Exa web search provider

tests/tools/test_web_search_tool.py

@@ -291,6 +291,71 @@ async def test_kagi_search(monkeypatch):
     assert "ignored related search" not in result
 
 
+@pytest.mark.asyncio
+async def test_exa_search(monkeypatch):
+    async def mock_post(self, url, **kw):
+        assert url == "https://api.exa.ai/search"
+        assert kw["headers"]["x-api-key"] == "exa-key"
+        assert kw["headers"]["User-Agent"] == "nanobot-search-test"
+        assert kw["json"] == {
+            "query": "test",
+            "numResults": 2,
+            "contents": {"highlights": True},
+        }
+        return _response(json={
+            "results": [
+                {
+                    "title": "Exa Result",
+                    "url": "https://exa.ai",
+                    "highlights": ["Relevant Exa highlight"],
+                }
+            ]
+        })
+
+    monkeypatch.setattr(httpx.AsyncClient, "post", mock_post)
+    tool = _tool(provider="exa", api_key="exa-key", user_agent="nanobot-search-test")
+    result = await tool.execute(query="test", count=2)
+
+    assert "Exa Result" in result
+    assert "https://exa.ai" in result
+    assert "Relevant Exa highlight" in result
+
+
+@pytest.mark.asyncio
+async def test_exa_search_uses_env_api_key(monkeypatch):
+    async def mock_post(self, url, **kw):
+        assert kw["headers"]["x-api-key"] == "env-exa-key"
+        return _response(json={
+            "results": [
+                {
+                    "title": "Env Exa Result",
+                    "url": "https://exa.ai/env",
+                    "summary": "Summary fallback",
+                }
+            ]
+        })
+
+    monkeypatch.setattr(httpx.AsyncClient, "post", mock_post)
+    monkeypatch.setenv("EXA_API_KEY", "env-exa-key")
+    tool = _tool(provider="exa", api_key="")
+    result = await tool.execute(query="test", count=1)
+
+    assert "Env Exa Result" in result
+    assert "Summary fallback" in result
+
+
+@pytest.mark.asyncio
+async def test_exa_search_http_error(monkeypatch):
+    async def mock_post(self, url, **kw):
+        return _response(status=401, json={"error": "invalid key"})
+
+    monkeypatch.setattr(httpx.AsyncClient, "post", mock_post)
+    tool = _tool(provider="exa", api_key="bad-exa-key")
+    result = await tool.execute(query="test")
+
+    assert "Error: Exa search failed (401)" in result
+
+
 @pytest.mark.asyncio
 async def test_unknown_provider():
     tool = _tool(provider="unknown")
@@ -377,6 +442,23 @@ async def test_kagi_fallback_to_duckduckgo_when_no_key(monkeypatch):
     assert "Fallback" in result
 
 
+@pytest.mark.asyncio
+async def test_exa_fallback_to_duckduckgo_when_no_key(monkeypatch):
+    class MockDDGS:
+        def __init__(self, **kw):
+            pass
+
+        def text(self, query, max_results=5):
+            return [{"title": "Fallback", "href": "https://ddg.example", "body": "DuckDuckGo fallback"}]
+
+    monkeypatch.setattr("ddgs.DDGS", MockDDGS)
+    monkeypatch.delenv("EXA_API_KEY", raising=False)
+
+    tool = _tool(provider="exa", api_key="")
+    result = await tool.execute(query="test")
+    assert "Fallback" in result
+
+
 @pytest.mark.asyncio
 async def test_jina_search_uses_path_encoded_query(monkeypatch):
     calls = {}