Enum HostError 

pub enum HostError {
    VersionMismatch {
        host: String,
        provider: String,
        provider_version: String,
    },
    Wire(String),
    Transport {
        id: String,
        message: String,
    },
    InsecureTransport {
        id: String,
        host: String,
    },
    Unauthorized {
        id: String,
    },
    ProviderCrashed {
        id: String,
    },
    Timeout {
        id: String,
        timeout_ms: u64,
    },
    Provider {
        id: String,
        code: Option<ErrorCode>,
        message: String,
    },
    ConsentRequired {
        id: String,
        data_flow: DataFlow,
    },
    ConsentScopeRequired {
        id: String,
        scopes: Vec<EgressScope>,
    },
    UnexpectedEnvelope {
        id: String,
        expected: String,
        got: String,
    },
    CorrelationMismatch {
        id: String,
        expected: String,
        got: String,
    },
    UnknownProvider(String),
    Spawn(String),
}

Anything the host runtime can surface while talking to a provider.

Variants

VersionMismatch

The provider speaks an incompatible protocol family (SPEC.md). Reported the instant the handshake ack arrives — never a hang (task deliverable 1).

Fields

host: String

provider: String

provider_version: String

Wire(String)

A line/body could not be encoded to or decoded from the wire envelope (SPEC.md §2). A malformed provider message is a clean error, never a host crash (task deliverable 5).

Transport

The underlying transport (stdio pipe or HTTP) failed.

Fields

id: String

message: String

InsecureTransport

The host refused to open a plaintext (http://) transport to a non-loopback provider (SPEC.md §4.2, C7): the query payload — and any bearer credential — would cross the network in cleartext. Raised before any bytes are sent, so nothing left the host. The message names only the id and host — never a credential (C8).

Fields

id: String

host: String

Unauthorized

The provider rejected the host’s bearer credential (HTTP 401). Distinct from a bare Transport failure so a host can react to an auth rejection specifically. The message names only the id and the status — never the credential itself (SPEC.md §4.2, C8).

Fields

id: String

ProviderCrashed

The provider’s child process closed its stream mid-exchange — it crashed. Isolated to this provider; never poisons a query_all (task deliverable 5).

Fields

id: String

Timeout

The provider took longer than the host’s per-provider budget.

Fields

id: String

timeout_ms: u64

Provider

The provider reported an error over the wire (an error envelope).

code carries the structured ErrorCode the provider sent (#9) so it survives the transport boundary instead of collapsing to a bare message; a host can then key its reaction (ErrorCode::reaction) off the code rather than sniffing the free-form string. None when the provider declared no code — read it as ErrorCode::Internal per SPEC.md.

Fields

id: String

code: Option<ErrorCode>

message: String

ConsentRequired

The provider declares egress and has no recorded consent, so the host refuses to transmit a query to it (SPEC.md SPEC.md §4 — a host MUST NOT auto-enable egress providers). The query payload never left the host.

Fields

id: String

data_flow: DataFlow

ConsentScopeRequired

The provider declares one or more off-machine egress scopes with no recorded consent receipt, so the host refuses to transmit a query to it (docs/context-reuse.md §3 — requirement C6). scopes names exactly the scopes that would leave unconsented. The query payload never left the host.

Fields

id: String

scopes: Vec<EgressScope>

UnexpectedEnvelope

A message of the wrong kind arrived where the protocol expected a specific envelope (e.g. a frames reply to a query).

Fields

id: String

expected: String

got: String

CorrelationMismatch

A provider that declared correlation answered without echoing the request’s id, or echoed the wrong one (SPEC.md §H4).

Fatal to the exchange rather than a warning: once replies cannot be matched to requests, a pipelining host could hand one caller’s frames to another, and silently mixing evidence between tasks is worse than failing the query.

Fields

id: String

expected: String

got: String

UnknownProvider(String)

No provider is registered under the given id.

Spawn(String)

Spawning the provider child process failed.

Trait Implementations

impl Debug for HostError

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

Formats the value using the given formatter.

impl Display for HostError

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

Formats the value using the given formatter.

impl Error for HostError

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.