Module protocol 

MCP protocol types based on JSON-RPC 2.0

These types follow the MCP specification (2025-11-25): https://modelcontextprotocol.io/specification/2025-11-25

Modules

notifications

MCP notification methods

Structs

BooleanSchema

Boolean field schema

CallToolParams

CallToolResult

Result of a tool invocation.

CancelTaskParams

Parameters for cancelling a task

CancelTaskResult

Result of cancelling a task

CancelledParams

Parameters for cancellation notification

ClientCapabilities

CompleteParams

Parameters for completion/complete request

CompleteResult

Result of completion/complete request

Completion

Completion suggestions

CompletionArgument

Argument being completed

CompletionsCapability

Server capability for providing completions

ContentAnnotations

Annotations for content items

CreateMessageParams

Parameters for sampling/createMessage request

CreateMessageResult

Result of sampling/createMessage request

ElicitFormParams

Parameters for form-based elicitation request

ElicitFormSchema

Restricted JSON Schema for elicitation forms

ElicitResult

Result of an elicitation request

ElicitUrlParams

Parameters for URL-based elicitation request

ElicitationCapability

Client capability for elicitation (requesting user input)

ElicitationCompleteParams

Parameters for elicitation complete notification

ElicitationFormCapability

Marker for form-based elicitation support

ElicitationUrlCapability

Marker for URL-based elicitation support

EmptyResult

EnqueueTaskParams

Parameters for enqueuing a task

EnqueueTaskResult

Result of enqueuing a task

GetPromptParams

GetPromptResult

GetPromptResultBuilder

Builder for constructing GetPromptResult with multiple messages.

GetTaskInfoParams

Parameters for getting task info

GetTaskResultParams

Parameters for getting task result

GetTaskResultResult

Result of getting task result

Implementation

Information about a client or server implementation

InitializeParams

InitializeResult

IntegerSchema

Integer field schema

JsonRpcErrorResponse

JSON-RPC 2.0 error response.

JsonRpcNotification

JSON-RPC 2.0 notification (no response expected)

JsonRpcRequest

JSON-RPC 2.0 request.

JsonRpcResultResponse

JSON-RPC 2.0 success response.

ListPromptsParams

ListPromptsResult

ListResourceTemplatesParams

Parameters for listing resource templates

ListResourceTemplatesResult

Result of listing resource templates

ListResourcesParams

ListResourcesResult

ListRootsParams

Parameters for roots/list request (server to client)

ListRootsResult

Result of roots/list request

ListTasksParams

Parameters for listing tasks

ListTasksResult

Result of listing tasks

ListToolsParams

ListToolsResult

LoggingCapability

Logging capability declaration

LoggingMessageParams

Parameters for logging message notification

ModelHint

Hint for model selection

ModelPreferences

Preferences for model selection during sampling

MultiSelectEnumItems

Items definition for multi-select enum

MultiSelectEnumSchema

Multi-select enum schema

NumberSchema

Number field schema

ProgressParams

Parameters for progress notification

PromptArgument

PromptDefinition

PromptMessage

PromptReference

Reference to a prompt for completion

PromptsCapability

ReadResourceParams

ReadResourceResult

RequestMeta

Request metadata that can include progress token

ResourceContent

Content of an embedded resource.

ResourceDefinition

ResourceReference

Reference to a resource for completion

ResourceTemplateDefinition

Definition of a resource template as returned by resources/templates/list

ResourcesCapability

Root

Represents a root directory or file that the server can operate on

RootsCapability

Client capability for roots (filesystem access)

SamplingCapability

SamplingMessage

Message for sampling request

SamplingTool

Tool definition for use in sampling requests (SEP-1577)

ServerCapabilities

SetLogLevelParams

Parameters for setting log level

SingleSelectEnumSchema

Single-select enum schema

StringSchema

String field schema

SubscribeResourceParams

TaskInfo

Information about a task

TaskStatusChangedParams

Notification params when task status changes

TasksCapability

Capability for async task management

ToolAnnotations

Annotations describing tool behavior for trust and safety. Clients MUST consider these untrusted unless the server is trusted.

ToolChoice

Tool choice mode for sampling requests (SEP-1577)

ToolDefinition

Tool definition as returned by tools/list

ToolIcon

Icon for tool display in user interfaces

ToolsCapability

UnsubscribeResourceParams

Enums

CompletionReference

Reference for completion - either a prompt or resource reference

Content

Content types for tool results, resources, and prompts.

ContentRole

Role indicating who content is intended for.

ElicitAction

User action in response to elicitation

ElicitFieldValue

Value from an elicitation form field

ElicitMode

Elicitation mode

ElicitRequestParams

Elicitation request parameters (union of form and URL modes)

IncludeContext

Context inclusion mode for sampling

JsonRpcMessage

JSON-RPC 2.0 message - can be a single request or a batch

JsonRpcResponse

JSON-RPC 2.0 response (either success or error).

JsonRpcResponseMessage

JSON-RPC 2.0 response message - can be a single response or a batch

LogLevel

Log severity levels following RFC 5424 (syslog)

McpNotification

High-level MCP notification (parsed from JSON-RPC)

McpRequest

High-level MCP request (parsed from JSON-RPC)

McpResponse

High-level MCP response

PrimitiveSchemaDefinition

Primitive schema definition for form fields

ProgressToken

Progress token - can be string or number

PromptRole

RequestId

Request ID - can be string or number per JSON-RPC spec

SamplingContent

Content types for sampling messages

SamplingContentOrArray

Content that can be either a single item or an array (for CreateMessageResult)

TaskStatus

Status of an async task

Constants

JSONRPC_VERSION

The JSON-RPC version. MUST be “2.0”.

LATEST_PROTOCOL_VERSION

The latest supported MCP protocol version.

SUPPORTED_PROTOCOL_VERSIONS

All supported MCP protocol versions (newest first).

Type Aliases

GetTaskInfoResult

Result of getting task info