Module protocol 

Agent Client Protocol wire types.

JSON-RPC 2.0 messages, newline-delimited, one compact message per line. Field names are camelCase and discriminator values are snake_case, per the spec.

Every type a client sends us is permissive on deserialize - unknown fields are ignored and every optional field carries #[serde(default)] - because real hosts differ in how much of the spec they populate. Gas City, for instance, sends initialize with only protocolVersion and clientInfo and no clientCapabilities at all.

Modules

error_codes

Standard JSON-RPC 2.0 error codes.

Structs

AgentCapabilities

Agent-side capabilities advertised at initialize.

AgentInfo

An agent’s identity.

ClientCapabilities

Client-side capabilities advertised at initialize.

ContentBlock

One block of prompt or message content.

EmbeddedResource

A resource inlined into a prompt (the embeddedContext capability).

InitializeParams

Params of the initialize request.

InitializeResult

Result of the initialize request.

JsonRpcError

A JSON-RPC 2.0 error object.

JsonRpcMessage

A JSON-RPC 2.0 message: request, response, or notification depending on which fields are set.

PermissionOption

One choice offered in a permission request.

PromptCapabilities

Prompt content kinds an agent accepts.

RequestPermissionParams

Params of an outbound session/request_permission request.

RequestPermissionResult

Result of a session/request_permission request.

SessionCancelParams

Params of the session/cancel notification.

SessionNewParams

Params of the session/new request.

SessionNewResult

Result of the session/new request.

SessionPromptParams

Params of the session/prompt request.

SessionPromptResult

Result of the session/prompt request.

SessionUpdateParams

Params of an outbound session/update notification.

ToolCallRef

The tool call a permission request refers to.

Enums

PermissionOptionKind

What selecting a permission option means.

PermissionOutcome

The user’s decision on a permission request.

SessionUpdate

One session/update payload, discriminated by sessionUpdate.

StopReason

Why a prompt turn ended.

ToolCallStatus

A tool call’s lifecycle status.

ToolKind

The category of operation a tool performs.

Constants

MAX_FRAME_BYTES

The largest single JSON frame (one line) we will ever write.

PROTOCOL_VERSION

The protocol MAJOR version this crate speaks.