You can now attach a JSON Schema to any string, number, or JSON flag to guarantee that every variation value has the shape you expect. When a schema is defined, LaunchDarkly validates variation changes against it and blocks any edit that doesn't conform — with a clear error message — in both the UI and the API.

Previously, LaunchDarkly checked only that a JSON variation was well-formed. Now you can enforce the structure of your values: required keys, value types, allowed enums, numeric ranges, and more. This helps teams who use flags as runtime configuration catch malformed values before they reach production.

What you can do:

• Add a schema at flag creation. When you create a string, number, or JSON flag, click Schema to define a JSON Schema for its variations.
• Add a schema to existing flags. On a flag's Variations tab, use Add schema to open the editor, with an inline preview and options to format, test, save, or remove the schema.
• Generate a schema automatically. Click the magic wand icon to suggest a JSON Schema based on your existing variation values, and the broom icon to format it.
• Enforce everywhere. Variation changes are validated both client-side and server-side, so edits made directly through the API, IaC, or scripts are protected too.

Schemas are visible on the flag's Variations page and in the flag sidebar, and all schema add, edit, and remove actions are recorded in the audit log.

Learn more in the documentation →