diff --git a/src/semble/cli.py b/src/semble/cli.py
index 509d99b..e9de6de 100644
--- a/src/semble/cli.py
+++ b/src/semble/cli.py
@@ -34,13 +34,18 @@ def _mcp_main() -> None:
         help="Local directory or git URL to pre-index at startup (optional).",
     )
     parser.add_argument("--ref", default=None, help="Branch or tag to check out (git URLs only).")
+    parser.add_argument(
+        "--include-text-files",
+        action="store_true",
+        help="Also index non-code text files (.md, .yaml, .json, etc.).",
+    )
     args = parser.parse_args()
     if any(find_spec(dep) is None for dep in get_package_extras("semble", "mcp")):
         print("MCP dependencies are not installed. Run: pip install 'semble[mcp]'", file=sys.stderr)
         raise SystemExit(1)
     from semble.mcp import serve
 
-    asyncio.run(serve(args.path, ref=args.ref))
+    asyncio.run(serve(args.path, ref=args.ref, include_text_files=args.include_text_files))
 
 
 def _run_init(*, force: bool = False) -> None:
@@ -66,12 +71,22 @@ def _cli_main() -> None:
     search_p.add_argument(
         "-m", "--mode", default="hybrid", choices=["hybrid", "semantic", "bm25"], help="Search mode (default: hybrid)."
     )
+    search_p.add_argument(
+        "--include-text-files",
+        action="store_true",
+        help="Also index non-code text files (.md, .yaml, .json, etc.).",
+    )
 
     related_p = sub.add_parser("find-related", help="Find code similar to a specific location.")
     related_p.add_argument("file_path", help="File path as shown in search results.")
     related_p.add_argument("line", type=int, help="Line number (1-indexed).")
     related_p.add_argument("path", nargs="?", default=".", help="Local path or git URL (default: current directory).")
     related_p.add_argument("-k", "--top-k", type=int, default=5, help="Number of results (default: 5).")
+    related_p.add_argument(
+        "--include-text-files",
+        action="store_true",
+        help="Also index non-code text files (.md, .yaml, .json, etc.).",
+    )
 
     init_p = sub.add_parser("init", help="Write .claude/agents/semble-search.md for Claude Code sub-agent support.")
     init_p.add_argument("--force", action="store_true", help="Overwrite if the file already exists.")
@@ -82,7 +97,12 @@ def _cli_main() -> None:
         _run_init(force=args.force)
         return
 
-    index = SembleIndex.from_git(args.path) if _is_git_url(args.path) else SembleIndex.from_path(args.path)
+    include_text = args.include_text_files
+    index = (
+        SembleIndex.from_git(args.path, include_text_files=include_text)
+        if _is_git_url(args.path)
+        else SembleIndex.from_path(args.path, include_text_files=include_text)
+    )
 
     if args.command == "search":
         results = index.search(args.query, top_k=args.top_k, mode=args.mode)
diff --git a/src/semble/mcp.py b/src/semble/mcp.py
index 42e814d..38d170c 100644
--- a/src/semble/mcp.py
+++ b/src/semble/mcp.py
@@ -116,10 +116,10 @@ async def find_related(
     return server
 
 
-async def serve(path: str | None = None, ref: str | None = None) -> None:
+async def serve(path: str | None = None, ref: str | None = None, include_text_files: bool = False) -> None:
     """Start an MCP stdio server, optionally pre-indexing a default source."""
     model = await asyncio.to_thread(load_model)
-    cache = _IndexCache(model=model)
+    cache = _IndexCache(model=model, include_text_files=include_text_files)
     if path:
         await cache.get(path, ref=ref)
         if not _is_git_url(path):
@@ -132,9 +132,10 @@ async def serve(path: str | None = None, ref: str | None = None) -> None:
 class _IndexCache:
     """Cache of indexed repos and local paths for the lifetime of the MCP server process."""
 
-    def __init__(self, model: Encoder) -> None:
+    def __init__(self, model: Encoder, include_text_files: bool = False) -> None:
         """Initialise an empty cache with a shared embedding model."""
         self._model = model
+        self._include_text_files = include_text_files
         self._tasks: OrderedDict[str, asyncio.Task[SembleIndex]] = OrderedDict()  # ordered for LRU eviction
         self._watcher_task: asyncio.Task[None] | None = None
 
@@ -173,11 +174,19 @@ async def get(self, source: str, ref: str | None = None) -> SembleIndex:
                 self._tasks.popitem(last=False)
             if _is_git_url(source):
                 self._tasks[cache_key] = asyncio.create_task(
-                    asyncio.to_thread(SembleIndex.from_git, source, ref=ref, model=self._model)
+                    asyncio.to_thread(
+                        SembleIndex.from_git,
+                        source,
+                        ref=ref,
+                        model=self._model,
+                        include_text_files=self._include_text_files,
+                    )
                 )
             else:
                 self._tasks[cache_key] = asyncio.create_task(
-                    asyncio.to_thread(SembleIndex.from_path, cache_key, model=self._model)
+                    asyncio.to_thread(
+                        SembleIndex.from_path, cache_key, model=self._model, include_text_files=self._include_text_files
+                    )
                 )
         task = self._tasks[cache_key]
         try: