Fix 3

server.py

@@ -96,7 +96,7 @@ async def get_document_url(doc_id: str, release: int = None):
     return output
     
 @mcp.tool()
-async def search_specs(keywords: str, limit: int, release: str = None, wg: str = None, spec_type: str = None, mode: str = "and"):
+async def search_specs(keywords: str, limit: int, release: str|None = None, wg: str|None = None, spec_type: str|None = None, mode: str = "and"):
     """
     Search 3GPP specifications only by their keywords [note that it will only work with keywords](and some filters [see kwargs field])
     Arguments available: keywords: string [mandatory, separated by space], limit [mandatory, default = 5], release: string [optional, filter] (the release version (e.g. 18, 9, 19, ...), generally the first number of the full version), wg: string [optional, filter] = working group (S1, C4, SP, ...), spec_type: string [optional, filter] (either TS or TR), mode [mandatory, default = 'and'] = search mode (and = all keywords must be in the search, or = at least one keyword in the search)