Scalar Adds OpenAPI 3.2 Support and Loads Stripe's Spec in 2 Seconds

Scalar’s API reference and API client now render OpenAPI 3.2 querystring parameters and additionalOperations, according to the project’s Sept. 24 release notes. A release the next day cut the time to load Stripe’s full API description from 17 seconds to about 2.

OpenAPI 3.2 features now render

The Sept. 24 release lists OpenAPI 3.2 support in @scalar/api-client 3.21.0 and @scalar/api-reference 1.72.0. The client handles querystring parameters, including content-based serialization, so a whole query string can be described as one JSON or form-encoded value. The reference shows additionalOperations in operation storage, navigation, documentation and callbacks.

The same release keeps a custom method intact in request URLs and code samples, and improves how discriminator mappings display and how code samples connect to their operations.

Stripe’s spec loads 8 times faster

Scalar’s Sept. 25 release says @scalar/openapi-to-markdown 1.3.0 loads Stripe’s API description in about 2 seconds with a peak of 190 MB of memory. The release notes put the old figures at 17 seconds and 1.4 GB. The package turns an OpenAPI document into Markdown for AI tools and credit changes that let heavily cross-linked descriptions load with far less heap.

Streaming and Markdown copy came first

Scalar’s API client now displays streaming responses, a change from its Sept. 22 release. JSON Lines, JSON Sequences and multipart responses now show parts as they arrive instead of after the full response. It also added a “Copy as Markdown” button to operations and webhooks in the reference, and a compact mode in @scalar/workspace-store that shrank one sparse document from 4.4 MB to 431 KB.

The Sept. 29 release was smaller: a helper for unescaping JSON Pointer segments, linked schema rendering in openapi-to-markdown, and higher text contrast in the Docusaurus integration.

Key takeaways

• Scalar’s Sept. 24 release renders OpenAPI 3.2 querystring parameters and additionalOperations.
• Stripe’s spec loads in about 2 seconds at 190 MB, down from 17 seconds at 1.4 GB, per the Sept. 25 notes.
• The API client displays JSON Lines, JSON Sequences and multipart responses as they stream, since Sept. 22.
• Operations and webhooks in the reference have a “Copy as Markdown” button.

The take

We think the 3.2 support matters more than the speedup. A team that adopts additionalOperations needs a renderer that shows those endpoints, or its documentation silently omits them. Scalar now does. We’d still load a real spec in the reference before relying on it, since the notes don’t say whether every 3.2 field is covered. The Stripe numbers are Scalar’s own, and we haven’t reproduced them.