vercel.json

`vercel doctor` validates whether the configuration items in `vercel.json` are valid.

vercel.toml supports exactly the same configuration properties as vercel.json, so the migration cost is low.

Vercel explicitly requires that each project use only one configuration file: vercel.toml, vercel.json or vercel.ts.

Vercel's schema is published with vercel.json as the baseline, so the vercel.toml file reuses the same JSON Schema address.

When migrating from vercel.json to vercel.toml, the old configuration file must be deleted, because only one configuration entry point is allowed per project.

Vercel announced that its projects can now be configured using a vercel.toml file, as another configuration option besides vercel.json.

vercel.toml is a configuration file used in Vercel projects to declare deployment behavior; like vercel.json it is a project-level configuration, but it uses TOML syntax, which is better suited to expressing nested structures and arrays of tables.

For multi-service projects, each service's `entrypoint` still needs to be configured via the `services` field in vercel.json, and the container runtime does not currently change this structure.

Developers can force a container build and override framework detection by running the `vercel project update --framework container` command or setting `"framework": "container"` in vercel.json.