# Vercel Flags now supports JSON values

**Published:** May 7, 2026 | **Authors:** Dominik Ferber, Chris Widmaier

---

You can now store JSON values in [Vercel Flags](https://vercel.com/docs/flags/vercel-flags), extending the existing support for boolean, string, and number values. This allows you to collapse what used to take several related flags into a single feature flag.

For example, to A/B test how a different model performs, you can now define a single `model` flag. This allows you to manage one flag that serves the full object rather than managing `ai_model`, `ai_temperature`, and `ai_max_tokens` separately:

```json
// Variant A
{
  "id": "claude-sonnet-4-6",
  "temperature": 0.7, 
  "maxTokens": 1024,
  "systemPrompt": "You are a helpful shopping assistant."
}
// Variant B
{
  "id": "claude-opus-4-6",
  "temperature": 0.8, 
  "maxTokens": 2048,
  "systemPrompt": "You help with shopping."
}
```

Use Vercel Flags to progressively route traffic to a new model, A/B test, or quickly switch models in case a provider is having issues.

[Try it out](https://vercel.com/d?to=%2F%5Bteam%5D%2F%5Bproject%5D%2Fflags&title=Vercel+Flags) or learn more about [Vercel Flags](https://vercel.com/docs/flags/vercel-flags).

---

📚 **More updates:** [View all changelog entries](/changelog/sitemap.md) | [Blog](/blog/sitemap.md)