Raise fetch_artifacts hard limit from 20 to 50, recommend ≤20 for context

Hard limit increased to 50 to support bulk fetches. Docstring recommends
≤20 to keep agent context size manageable — agents should prefer smaller
batches unless they specifically need more.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: rodion-m

src/tests/test_e2e_tools.py

@@ -748,16 +748,17 @@ async def test_empty_identifiers_returns_error(self):
         assert "required" in _text(result).lower() or "error" in _text(result).lower()
 
     @pytest.mark.asyncio
-    async def test_over_20_identifiers_rejected(self):
+    async def test_over_50_identifiers_rejected(self):
         mcp = _server({})
         async with Client(mcp) as client:
             result = await client.call_tool(
                 "fetch_artifacts",
-                {"identifiers": [f"id-{i}" for i in range(21)]},
+                {"identifiers": [f"id-{i}" for i in range(51)]},
                 raise_on_error=False,
             )
 
-        assert "20" in _text(result) or "Maximum" in _text(result)
+        assert result.is_error
+        assert "50" in _text(result) or "Maximum" in _text(result)
 
     @pytest.mark.asyncio
     async def test_artifact_with_relationships(self):

src/tests/test_fetch_artifacts.py

@@ -435,9 +435,9 @@ async def test_fetch_artifacts_exceeds_max_identifiers():
     """Test that more than 20 identifiers raises ToolError."""
     ctx = MagicMock(spec=Context)
 
-    identifiers = [f"owner/repo::file{i}.py::func{i}" for i in range(21)]
+    identifiers = [f"owner/repo::file{i}.py::func{i}" for i in range(51)]
 
-    with pytest.raises(ToolError, match="Maximum 20"):
+    with pytest.raises(ToolError, match="Maximum 50"):
         await fetch_artifacts(ctx=ctx, identifiers=identifiers)
 
 

src/tools/fetch_artifacts.py

@@ -63,7 +63,8 @@ async def fetch_artifacts(
         gives the total. Relationships are omitted for non-function artifacts.
 
     Note:
-        - Maximum 20 identifiers per request to avoid excessive payloads.
+        - Hard limit: 50 identifiers per request. Recommended: ≤20 to keep
+          context size manageable and avoid flooding the conversation with code.
         - Identifiers must come from `semantic_search`, `grep_search`, or legacy `codebase_search` results.
         - Relationships shown here are a **preview** (up to 3 call relationships per direction).
           To retrieve the complete list, or to explore other relationship types
@@ -76,8 +77,8 @@ async def fetch_artifacts(
     if not identifiers:
         raise ToolError(f"[{_TOOL_NAME}] At least one identifier is required.")
 
-    if len(identifiers) > 20:
-        raise ToolError(f"[{_TOOL_NAME}] Maximum 20 identifiers per request. Please reduce the number of identifiers.")
+    if len(identifiers) > 50:
+        raise ToolError(f"[{_TOOL_NAME}] Maximum 50 identifiers per request. Please reduce the number of identifiers.")
 
     context: CodeAliveContext = ctx.request_context.lifespan_context