GraphQL

GraphQL is a query language for APIs and a runtime for fulfilling those queries against your existing data. Originally developed at Facebook in 2012 and open-sourced in 2015, it lets a client ask for exactly the fields it needs in a single request against a strongly typed schema, in contrast to the fixed, resource-oriented responses of a typical REST API. It is now governed by the GraphQL Foundation under the Linux Foundation.

• A typed schema as the contract - Every GraphQL API is defined by a schema of types and fields that both documents and validates the data available.
• Client-specified queries - Consumers request precisely the fields they want, avoiding the over- and under-fetching common with fixed endpoints.
• A single endpoint - Queries, mutations, and subscriptions all flow through one URL rather than a sprawl of resource paths.
• Introspection - The schema is queryable at runtime, which powers tooling, documentation, and increasingly agent discovery.

In real API operations GraphQL shows up as one protocol among several a provider will offer, alongside REST and increasingly gRPC and event-driven interfaces, which is why I keep coming back to multi-protocol governance rather than treating any one style as the answer. Its typed schema and introspection make it attractive for AI agents that need to discover and shape their own queries, but the same flexibility that helps consumers also complicates rate limiting, caching, and authorization, so it demands deliberate governance rather than adoption by dogma.