Scalar is a platform for building and managing API specifications, focusing on OpenAPI and AsyncAPI standards. It provides tools to generate interactive API references with embedded testing interfaces, create mock servers for pre-implementation testing, and build offline-first API clients that sync with backend frameworks. The platform also supports version upgrades of specifications to maintain compatibility and includes command-line utilities for local development and document management.
The project distinguishes itself through automated release workflows that generate changelogs and publish npm packages based on version changes. It offers SDK generation from API specs, CDN-based distribution of documentation with custom domain support, and security features for vulnerability reporting and triage. Scalar’s framework integrations allow developers to import specifications directly into code and render default documentation UIs for supported environments.
Scalar includes tools for converting API documents to Markdown and HTML formats, and it provides standardized example documents for both OpenAPI and AsyncAPI to aid in learning and testing. These capabilities extend to real-time HTTP request inspection and WebSocket communication validation through dedicated mirror servers.
The CLI tools enable local serving of API documentation, automatically refreshing when files change, and the project’s documentation covers integration with web frameworks and specification conversion workflows.
