# Errors > UForm for Swift `UFormError` is the only error the SDK throws, and every method says so with `throws(UFormError)`, so a `catch` reads `error.status` with no cast. `Status` has one constant per `uform_status_*_k` of the C interface, and its `description` spells it as the library does, like `invalid-argument`. ```swift do { _ = try Model.loadRam(path: "missing.safetensors") } catch { print(error.status, error.message) // io The checkpoint could not be opened for reading } ``` `Scalar`, `Mood` and every other closed set read a spelling back with `init?(name:)`, and nil for one the library does not spell. `import UForm` ## Status What went wrong, in the vocabulary the library and every binding share - one constant per `uform_status_*_k`, carrying the C enumerator itself. ```swift struct Status ``` A [`UFormError`](#UFormError) never carries [`success`](#success) or [`deferred`](#deferred); a [`Deferred`](https://www.unum.cloud/docs/uform/swift/receivers-and-deferred-calls.md#Deferred) call reports both. Conforms to: `Hashable`, `Sendable`, `CustomStringConvertible`, `Equatable` ## success The call succeeded and carries no message. ```swift static let success: Status ``` ## deferred The call was submitted deferred and is not final yet. ```swift static let deferred: Status ``` ## outOfMemory Device, pinned or host memory could not be allocated. ```swift static let outOfMemory: Status ``` ## shapeMismatch Item counts, a pixel shape or a batch envelope disagree with the call or the model. ```swift static let shapeMismatch: Status ``` ## unsupportedLayout A stride or packing the model cannot read. ```swift static let unsupportedLayout: Status ``` ## unknownKind A scalar, modality or name this build does not know. ```swift static let unknownKind: Status ``` ## io A checkpoint file could not be opened, read or written. ```swift static let io: Status ``` ## device The driver refused or the device faulted. ```swift static let device: Status ``` ## malformed Supplied bytes could not be decoded. ```swift static let malformed: Status ``` ## internal The library reported neither success nor a failure. ```swift static let `internal`: Status ``` ## configMismatch The request contradicts a frozen configuration. ```swift static let configMismatch: Status ``` ## contended A call was refused rather than waited for - a full deferred table, or an arena serving another call. ```swift static let contended: Status ``` ## cancelled A progress handler asked the call to stop; it unwound and published nothing. ```swift static let cancelled: Status ``` ## unsupported The verb is declared, but this residency or model does not implement it. ```swift static let unsupported: Status ``` ## invalidArgument An argument breaks the verb's contract. ```swift static let invalidArgument: Status ``` ## description The status as the library spells it, like `invalid-argument`. ```swift var description: String { get } ``` Calls `uform_status_name`. ## init Reads a spelling back, and nil for one no status carries. ```swift init?(name: String) ``` Calls `uform_status_from_name`. ## UFormError One failed call: a status every caller can branch on, and the detail the status cannot carry. ```swift struct UFormError ``` Conforms to: `Error`, `CustomStringConvertible`, `Equatable`, `Sendable` ## status The failure identity, shared with every other SDK. ```swift let status: Status ``` ## message The library's static detail, or this binding's own when it refused the call. ```swift let message: String ``` ## description The status and message, as `uform: : `. ```swift var description: String { get } ```