Error codes

The wire error type is SuperLineError from @super-line/core. Throw one from a handler and the client's promise rejects with the same code (and optional data). For usage — throwing, catching, custom codes — see Handle errors.

import { SuperLineError } from '@super-line/core'
throw new SuperLineError('FORBIDDEN', 'not a member', { room })
//                        code         message         optional data

Built-in codes

SuperLineErrorCode is the built-in set; code also accepts any custom string.

Code	Meaning	Typical source
BAD_REQUEST	malformed / unprocessable request	a bad or aborted call
UNAUTHORIZED	not authenticated	authenticate rejected the handshake
FORBIDDEN	authenticated but not allowed	a denied subscribe or a policy/guard
NOT_FOUND	no such request/topic for this role	a cross-role call, an unopened doc
TIMEOUT	no reply within the deadline	a request that exceeded timeoutMs
VALIDATION	payload failed its schema	inbound input/payload rejected
DISCONNECTED	the connection dropped	socket lost before the reply
INTERNAL	unexpected server error	an unknown throw in a handler (details not leaked)

An unknown throw from a handler becomes INTERNAL so server internals aren't exposed. Custom codes are just strings — throw new SuperLineError('RATE_LIMITED', …) — and reach the client verbatim.

See the API reference for the class surface.