JSON Schema Lint is a JSON schema validator to help you write and test of
JSON Schemas that conform with the Draft v4 specification, with partial support for the work-in-progress v5 specification.
The author/maintainer is Nick Maynard. Fork this project on Github.
Under the covers, it uses Evgeny Poberezkin's Ajv library, passed through Browserify to make it work in the browser.
Optionally, you may use schemas and documents in the YAML format. These documents are parsed with Jérémy Fairve's yaml.js library.