REST or MCP?
Both interfaces expose the same underlying ownership data. The right one depends on who's asking the questions.
Use the REST API when…
- you're loading data into a warehouse, model or product feature,
- you want entire markets at once (the ownership endpoints stream hundreds of thousands of rows),
- you need CSV/XML for existing tooling, or
- a scheduled job consumes the data without a human (or agent) in the loop.
Authentication is a static API key, and your contract defines exactly which endpoints, parameters and fields you can use.
Use the MCP server when…
- an AI agent (Claude, ChatGPT, or anything MCP-capable) should answer ad-hoc questions with live data,
- you want per-question access, like "who has been buying Volvo this quarter?", without building an integration,
- usage should be metered by returned result units (credits) rather than provisioned as bulk access.
Authentication is OAuth 2.1 with scoped tokens, and returned result units are billed in Dataflow credits against a monthly cap.
Use both
Most customers do: the REST API feeds the systems, the MCP server feeds the people. Both interfaces share entity IDs: a company_id from the MCP search_securities tool is the same ID the REST endpoints use, so workflows can cross between them freely.