External adapters are how Chainlink enables easy integration of custom computations and specialized APIs. External adapters are services which the core of the Chainlink node communicates via its API with a simple JSON specification.

Information on external adapters is broken up into three main categories: contract creators, developers, and node operators.

• Contract Creators will need to know how to specify an external adapter in their request for external data.
• Developers will need to know how to implement an external adapter for an API.
• Node Operators will need to know how to add an external adapter to their node so that they can provide specialized services to smart contracts.