diff --git a/code_review_graph/main.py b/code_review_graph/main.py
index 733336e1..5671244f 100644
--- a/code_review_graph/main.py
+++ b/code_review_graph/main.py
@@ -43,7 +43,6 @@
     get_suggested_questions_func,
     get_surprising_connections_func,
     get_wiki_page_func,
-    traverse_graph_func,
     list_communities_func,
     list_flows,
     list_graph_stats,
@@ -52,6 +51,7 @@
     refactor_func,
     run_postprocess,
     semantic_search_nodes,
+    traverse_graph_func,
 )
 
 # NOTE: Thread-safe for stdio MCP (single-threaded). If adding HTTP/SSE
@@ -155,7 +155,7 @@ async def run_postprocess_tool(
 
 
 @mcp.tool()
-def get_minimal_context_tool(
+async def get_minimal_context_tool(
     task: str = "",
     changed_files: Optional[list[str]] = None,
     repo_root: Optional[str] = None,
@@ -167,15 +167,21 @@ def get_minimal_context_tool(
     next tools in a single compact response. Use this as the entry point
     before any other graph tool to minimize token usage.
 
+    Offloaded to a thread via ``asyncio.to_thread`` so git diff / analyze_changes
+    don't block the stdio event loop. See: #46, #136.
+
     Args:
         task: What you are doing (e.g. "review PR #42", "debug login timeout").
         changed_files: Explicit list of changed files. Auto-detected if omitted.
         repo_root: Repository root path. Auto-detected if omitted.
         base: Git ref for diff comparison. Default: HEAD~1.
     """
-    return get_minimal_context(
-        task=task, changed_files=changed_files,
-        repo_root=_resolve_repo_root(repo_root), base=base,
+    return await asyncio.to_thread(
+        get_minimal_context,
+        task=task,
+        changed_files=changed_files,
+        repo_root=_resolve_repo_root(repo_root),
+        base=base,
     )
 
 
diff --git a/tests/test_main.py b/tests/test_main.py
index 61fbbf49..62bbe171 100644
--- a/tests/test_main.py
+++ b/tests/test_main.py
@@ -59,7 +59,7 @@ def fake_run(**kwargs):
 
         monkeypatch.setattr(crg_main.mcp, "run", fake_run)
         crg_main.main(repo_root=None)
-        assert calls == [{"transport": "stdio"}]
+        assert calls == [{"transport": "stdio", "show_banner": False}]
 
     def test_http_calls_mcp_run_with_host_port(self, monkeypatch):
         calls: list[dict] = []
@@ -103,6 +103,7 @@ class TestLongRunningToolsAreAsync:
         "embed_graph_tool",
         "detect_changes_tool",
         "generate_wiki_tool",
+        "get_minimal_context_tool",
     }
 
     def test_heavy_tools_are_coroutines(self):