Configuration

Runtime configuration

createClient accepts:

• baseUrl?: string
• headers?: HeadersInit
• fetch?: typeof fetch

Generator configuration

generateSdk and the CLI support:

• input from file or url
• outputDir
• sdkName
• baseUrl
• clean
• dryRun: return formatted files without writing
• check: compare against disk; inspect result.changedFiles
• schemaTimeoutMs (core) / --timeout (CLI): remote schema deadline, default 30 seconds
• signal (core): cancel schema downloads
• logger (core) / --verbose (CLI)

Supported OpenAPI features

• openapi
• info
• servers
• paths
• components.schemas
• GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS
• string, number, integer, boolean, array, object, enum, nullable
• anyOf, oneOf, allOf, dictionaries and nullable objects
• local component $ref, including escaped JSON Pointer names and alias chains
• recursive model references; alias cycles produce a validation error
• query arrays: form (repeated keys by default, comma separated with explode: false), spaceDelimited, pipeDelimited

Request options and errors

Pass RequestInit as the second argument to a method with a request object (or as the first argument for methods without parameters). This includes signal, credentials and per-request headers. Per-request headers override client headers. ApiError exposes status, headers and body, preserving the raw response when an error server incorrectly labels non-JSON content as JSON.

Limitations

This is a subset generator, not a complete OpenAPI validator. The type model targets OpenAPI 3.0; OpenAPI 3.1-specific JSON Schema keywords such as type: [string, null], const and boolean schemas are not implemented. Convert such schemas to the supported 3.0 constructs before generation.

• External file/URL references and path-level references are unsupported.
• Request bodies support JSON media types, including +json; multipart and form bodies are unsupported.
• Only the first successful response is modeled (or the first response when no success is declared); non-JSON response schemas are not modeled.
• Header/cookie parameters and security schemes are not generated. Supply authentication and headers through client configuration or RequestInit.
• Object query parameters and custom path serialization are unsupported; path values use simple string encoding.
• Server variables are not expanded; use --base-url with a concrete absolute URL.
• TRACE is unavailable through standard fetch and is rejected.

The CLI reports duplicate normalized operation names and component type names. If an operation request/response type conflicts with a component, it receives a numeric suffix (for example CreateUserRequest2). Components keep their names.

--clean removes the output directory: use a dedicated generated directory. It rejects the working directory, its ancestors, the home directory and directories containing the local input schema, resolving existing ancestor symlinks when checking protected paths. Output-root and nested symlinks are rejected. Files are replaced atomically; the directory as a whole is not a transaction. Cyclic YAML aliases are rejected; use OpenAPI $ref for recursive models. --check and --dry-run perform no writes.