diff --git a/core/src/utcp/implementations/tag_search.py b/core/src/utcp/implementations/tag_search.py
index f11bf40..7113f51 100644
--- a/core/src/utcp/implementations/tag_search.py
+++ b/core/src/utcp/implementations/tag_search.py
@@ -39,7 +39,7 @@ async def search_tools(self, tool_repository: ConcurrentToolRepository, query: s
         Args:
             tool_repository: The tool repository to search in.
             query: The query to search for.
-            limit: The maximum number of results to return.
+            limit: The maximum number of results to return. Use 0 for no limit.
             any_of_tags_required: A list of tags that must be present in the tool.
 
         Returns:
@@ -91,8 +91,8 @@ async def search_tools(self, tool_repository: ConcurrentToolRepository, query: s
         # Sort tools by score in descending order
         sorted_tools = [tool for tool, score in sorted(tool_scores, key=lambda x: x[1], reverse=True)]
         
-        # Return up to 'limit' tools
-        return sorted_tools[:limit]
+        # Return up to 'limit' tools (0 for no limit)
+        return sorted_tools[:limit] if limit > 0 else sorted_tools
 
 class TagAndDescriptionWordMatchStrategyConfigSerializer(Serializer[TagAndDescriptionWordMatchStrategy]):
     """REQUIRED
diff --git a/core/src/utcp/implementations/utcp_client_implementation.py b/core/src/utcp/implementations/utcp_client_implementation.py
index e494b6e..9d62826 100644
--- a/core/src/utcp/implementations/utcp_client_implementation.py
+++ b/core/src/utcp/implementations/utcp_client_implementation.py
@@ -442,7 +442,7 @@ async def search_tools(self, query: str, limit: int = 10, any_of_tags_required:
 
         Args:
             query: The query to search for.
-            limit: The maximum number of results to return.
+            limit: The maximum number of results to return. 0 for no limit.
             any_of_tags_required: A list of tags that must be present in the tool.
 
         Returns:
diff --git a/core/tests/implementations/test_tag_search.py b/core/tests/implementations/test_tag_search.py
new file mode 100644
index 0000000..94be080
--- /dev/null
+++ b/core/tests/implementations/test_tag_search.py
@@ -0,0 +1,100 @@
+"""Unit tests for TagAndDescriptionWordMatchStrategy."""
+
+import pytest
+from utcp.data.call_template import CallTemplate
+from utcp.data.tool import Tool, JsonSchema
+from utcp.data.utcp_manual import UtcpManual
+from utcp.implementations.in_mem_tool_repository import InMemToolRepository
+from utcp.implementations.tag_search import TagAndDescriptionWordMatchStrategy
+
+
+def get_sample_tools():
+    tpl = CallTemplate(name="test_manual", call_template_type="test")
+    return [
+        Tool(
+            name="add_numbers",
+            description="Add two numbers together in arithmetic",
+            inputs=JsonSchema(type="object"),
+            outputs=JsonSchema(type="object"),
+            tool_call_template=tpl,
+            tags=["math", "addition", "calculator"],
+        ),
+        Tool(
+            name="subtract_numbers",
+            description="Subtract two numbers in arithmetic",
+            inputs=JsonSchema(type="object"),
+            outputs=JsonSchema(type="object"),
+            tool_call_template=tpl,
+            tags=["math", "subtraction", "calculator"],
+        ),
+        Tool(
+            name="send_email",
+            description="Send an email to a recipient",
+            inputs=JsonSchema(type="object"),
+            outputs=JsonSchema(type="object"),
+            tool_call_template=tpl,
+            tags=["communication", "email"],
+        ),
+    ]
+
+
+async def create_populated_repo():
+    tools = get_sample_tools()
+    repo = InMemToolRepository()
+    tpl = CallTemplate(name="test_manual", call_template_type="test")
+    manual = UtcpManual(tools=tools)
+    await repo.save_manual(tpl, manual)
+    return repo, tools
+
+
+@pytest.mark.asyncio
+async def test_search_tools_limit_zero_returns_all_tools():
+    """Verify limit=0 returns all matching tools without slicing to empty."""
+    repo, tools = await create_populated_repo()
+    strategy = TagAndDescriptionWordMatchStrategy()
+    results = await strategy.search_tools(repo, "math", limit=0)
+    assert len(results) == len(tools)
+
+
+@pytest.mark.asyncio
+async def test_search_tools_positive_limit_respected():
+    """Verify limit > 0 returns at most `limit` results."""
+    repo, _ = await create_populated_repo()
+    strategy = TagAndDescriptionWordMatchStrategy()
+    results = await strategy.search_tools(repo, "math", limit=1)
+    assert len(results) == 1
+    assert results[0].name in ("add_numbers", "subtract_numbers")
+
+
+@pytest.mark.asyncio
+async def test_search_tools_negative_limit_raises_error():
+    """Verify negative limit raises ValueError."""
+    repo, _ = await create_populated_repo()
+    strategy = TagAndDescriptionWordMatchStrategy()
+    with pytest.raises(ValueError, match="limit must be non-negative"):
+        await strategy.search_tools(repo, "math", limit=-1)
+
+
+@pytest.mark.asyncio
+async def test_search_tools_tag_and_description_matching():
+    """Verify tools with matching tags rank highest."""
+    repo, _ = await create_populated_repo()
+    strategy = TagAndDescriptionWordMatchStrategy()
+    results = await strategy.search_tools(repo, "email", limit=10)
+    assert len(results) > 0
+    assert results[0].name == "send_email"
+
+
+@pytest.mark.asyncio
+async def test_search_tools_any_of_tags_required():
+    """Verify any_of_tags_required filters out non-matching tools."""
+    repo, _ = await create_populated_repo()
+    strategy = TagAndDescriptionWordMatchStrategy()
+    results = await strategy.search_tools(
+        repo,
+        "numbers",
+        limit=0,
+        any_of_tags_required=["addition"],
+    )
+    assert len(results) == 1
+    assert results[0].name == "add_numbers"