GraphQL Validator

The GraphQL Validator analyzes a provided query against a target endpoint to verify correctness and conformance. It detects syntax errors, invalid field references, and type mismatches, highlighting the exact location in the query. It supports variables, headers, and operation names, enabling developers to validate single queries or batch requests in a staging environment. It returns structured feedback with error codes and suggested fixes.\n\nInternally, the tool parses the query into an AST, optionally requests a live schema via introspection, and applies GraphQL rules to validate structure and types. When a schema is available, it checks field existence, argument types, and fragment composition; when not, it performs syntax and reference checks only. It supports multiple operations, operation name disambiguation, and consistent error reporting.\n\nThis tool benefits API developers, frontend and mobile teams, and QA engineers who integrate GraphQL into services and apps. Its value lies in early error detection, actionable diagnostics, and repeatable validation that can slip into CI pipelines or API testing workflows, reducing debugging time and preventing runtime failures. It can also be used to compare responses across environments for contract verification.\n\nKey features include endpoint-aware validation, variable handling, header configuration, optional schema introspection, precise error localization with line and column, and exportable results for downstream tooling. Typical use cases are validating new queries, verifying schema changes, confirming client expectations align with server capabilities, and pre-deployment checks in automated testing.