Configuration Reference

ads-mcp is configured entirely through environment variables. The recommended approach is to place them in a .env file next to wherever you run the server; the server loads this file automatically via python-dotenv.

Variables

ADS_API_TOKEN (required)

Your ADS API bearer token. Obtain one at https://ui.adsabs.harvard.edu/user/settings/token.

ADS_API_TOKEN=your_key_here

Warning

Keep this value secret. Do not commit it to version control.

ADS_MCP_LOG_LEVEL (optional)

Python log level for the server process.

Value

Effect

DEBUG

Very verbose output; useful for development

INFO

Informational messages

WARNING

(default) Warnings and errors only

ERROR

Errors only

ADS_MCP_LOG_LEVEL=WARNING

Rate limits

ADS API access is rate-limited per endpoint (typically 5,000 requests per day for search). The HTTP response headers X-RateLimit-Limit, X-RateLimit-Remaining, and X-RateLimit-Reset report the current status. If you exceed the limit you will receive an ADSError with status 429.

Contact adshelp@cfa.harvard.edu if you need higher limits for a research project.