| USGS_USER_AGENT | No | Custom User-Agent string for USGS requests (NWIS and the parameter-code catalog). Defaults to a descriptive identifier including the repo URL. |
| USGS_REQUEST_TIMEOUT_MS | No | HTTP request timeout in milliseconds for USGS calls (NWIS and the parameter-code catalog). Default: 30000. |
| WATER_DATAFRAME_DROP_ENABLED | No | Set to true to make water_dataframe_drop callable — it removes one staged table from a DataCanvas. Off by default, which lists the tool as disabled. Needs CANVAS_PROVIDER_TYPE=duckdb to have anything to drop. |
| MCP_LOG_LEVEL | No | Sets the minimum log level for output (e.g., 'debug', 'info', 'warn'). |
| MCP_TRANSPORT_TYPE | No | Selects the HTTP transport. |
| USGS_USER_AGENT | No | Custom User-Agent string for USGS requests (NWIS and the parameter-code catalog). Defaults to a descriptive identifier including the repo URL. |
| USGS_REQUEST_TIMEOUT_MS | No | HTTP request timeout in milliseconds for USGS calls (NWIS and the parameter-code catalog). Default: 30000. |
| WATER_DATAFRAME_DROP_ENABLED | No | Set to true to make water_dataframe_drop callable — it removes one staged table from a DataCanvas. Off by default, which lists the tool as disabled. Needs CANVAS_PROVIDER_TYPE=duckdb to have anything to drop. |
| MCP_HTTP_HOST | No | The hostname for the HTTP server. |
| MCP_HTTP_PORT | No | The port to run the HTTP server on. |
| MCP_HTTP_ENDPOINT_PATH | No | The endpoint path for the MCP server. |
| MCP_AUTH_MODE | No | Authentication mode to use: 'none', 'jwt', or 'oauth'. |
| MCP_LOG_LEVEL | No | Sets the minimum log level for output (e.g., 'debug', 'info', 'warn'). |