- Tushare: Added /test endpoint to verify API token validity by fetching a small dataset.
- AlphaVantage: Implemented custom HTTP transport to handle MCP server's 400 Bad Request response on SSE endpoint gracefully (degrading to POST-only mode).
- AlphaVantage: Added /test endpoint using `list_tools` to verify MCP connection.
- AlphaVantage: Updated configuration polling to support dynamic API URLs.