Enum Error 

pub enum Error {
    Config(String),
    Provider {
        status: u16,
        body: String,
        retry_after: Option<Duration>,
    },
    Network(String),
    Decode(String),
    Encode(String),
    Invalid(String),
    Unsupported(String),
    Routing(String),
    Timeout,
    Internal(String),
}

Shared error type for the crabllm workspace.

Every variant carries enough structure that retry semantics (Error::is_transient), HTTP status (Error::http_status), and the client-facing error type (Error::kind) are derivable from the variant alone — never from string contents. Layers must NOT stringify-and-rewrap an inner error (Error::Internal(format!("...: {e}"))); propagate the inner Error or classify the cause into the right variant instead.

Variants

Config(String)

TOML config parse error or missing env var. Startup only.

Provider

Upstream provider returned (or streamed) an error. body is the upstream’s own message, passed through verbatim — never prefixed.

Fields

status: u16

body: String

retry_after: Option<Duration>

Network(String)

Transport failure talking to the upstream: connect, send, or reading a (possibly mid-stream) response body. Transient.

Decode(String)

An upstream response body could not be deserialized into our types. Not transient — retrying yields the same unparseable bytes.

Encode(String)

Our own request could not be serialized. A bug on our side, not the upstream’s. Not transient.

Invalid(String)

The client’s request is malformed or violates a precondition (e.g. a body that doesn’t match the schema, or an unsupported option combination). The client’s fault — not transient, 400.

Unsupported(String)

A provider does not implement the requested operation.

Routing(String)

Request could not be routed: unknown model or no matching deployment.

Timeout

Request to upstream provider timed out.

Internal(String)

Genuine catch-all for internal bugs. Not transient — if it happens, retrying won’t help.

Implementations

impl Error

pub fn is_transient(&self) -> bool

Whether this error is transient and the request should be retried. Only network failures, timeouts, and upstream 429/5xx are transient; everything else (decode, encode, unsupported, routing, internal) is deterministic and must not be retried.

pub fn retry_after(&self) -> Option<Duration>

Extract the retry-after duration from a Provider error, if present.

pub fn http_status(&self) -> u16

HTTP status to return to the client for this error. Single source of truth for the proxy’s error-to-response mapping.

pub fn kind(&self) -> &'static str

OpenAI-compatible error type for the client-facing ApiError.

pub fn not_implemented(method: &str) -> Self

Build an “operation not supported” error for a provider trait method that has no implementation. Used by Provider trait default impls. Distinct from per-provider rejection messages so log lines can be disambiguated by grep.

Trait Implementations

impl Debug for Error

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for Error

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for Error

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.