Does Mock API Studio execute submitted TypeScript?

No. It analyzes declarations without emitting or evaluating JavaScript, and rejects executable declarations and side-effect imports.

Schema guide

Create Mock APIs from TypeScript Schemas

Mock API Studio reads serializable TypeScript interfaces, type aliases, and enums and turns an exported response type into a mock REST resource. Define the contract in the model workspace, validate it, and bind the exported type to an endpoint before starting the local runtime.

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Which TypeScript types can define a mock API?

Use interfaces, type aliases, string enums, primitive fields, arrays, nested object literals, optional fields, nullable fields, and supported unions. Multi-file projects can use relative imports and re-exports, while external packages and executable declarations are intentionally rejected.

TypeScript

export interface Product {
  id: string;
  name: string;
  price: number;
  status: "draft" | "active";
  tags?: string[];
}

export type ProductResponse = Product[];

Create or import model files

Create .ts files in the project model workspace or import a file tree. Imports keep project-relative paths. The browser editor reports TypeScript diagnostics, while server validation remains authoritative before a model is used.

Keep domain models in focused files.
Export every type that must be available to an endpoint binding.
Use exact filename casing because project paths are case-sensitive.

Bind a response type to an endpoint

Choose the source file and exported type in the endpoint editor, then select collection or single-object response shape. This explicit binding avoids guessing which declaration represents the response.

Configuration

Route: /products
Source: models/product.ts
Export: Product
Response shape: collection
Operations: GET, POST, PATCH, DELETE

Validate before local synchronization

Validation catches missing exports, invalid generic arguments, unsupported recursion, index signatures, and endpoint settings that reference unavailable fields. Resolve errors before restarting the CLI; the local runtime synchronizes the current valid project definition.

Keep exploring

Last updated September 17, 2026. Product behavior described here is verified against the current Mock API Studio runtime.