mcp_models_v2026 library
Dart models for the MCP (Model Context Protocol) 2026-07-28 schema.
Classes
- Annotations
- Optional client hints attached to MCP content objects.
- AudioContent
- Audio content block for LLM interactions.
- BlobResourceContents
- Binary resource content encoded as base64.
- BooleanSchema
-
The MCP
BooleanSchemaschema type. - CallToolRequest
-
A
tools/callJSON-RPC request. - CallToolRequestParams
-
Parameters for a
tools/callrequest. - CallToolResult
-
The server's response to a
tools/callrequest. - CallToolResultOutcome
-
Discriminated union: either an InputRequiredResult pause or the
completed CallToolResult, as returned by
CallToolResultResponse.result. - CallToolResultResponse
- A successful response from the server for a tools/call request.
- CancelledNotification
- Sent by the client to indicate it is cancelling a previously-issued request.
- CancelledNotificationParams
- Parameters for a notifications/cancelled notification.
- ClientCapabilities
- Capabilities declared by the MCP client.
- CompleteRequest
- A request from the client to the server, to ask for completion options.
- CompleteRequestParams
- Parameters for a completion/complete request.
- CompleteRequestParamsArgument
-
The MCP
CompleteRequestParamsArgumentschema type. - CompleteRequestParamsContext
-
The MCP
CompleteRequestParamsContextschema type. - CompleteResult
- The result returned by the server for a completion/complete request.
- CompleteResultCompletion
-
The MCP
CompleteResultCompletionschema type. - CompleteResultResponse
- A successful response from the server for a completion/complete request.
- ContentBlock
- Base class for all MCP content blocks (text, image, audio, resource, etc.).
- CreateMessageRequest
- A request from the server to sample an LLM via the client.
- CreateMessageRequestParams
- Parameters for a sampling/createMessage request.
- CreateMessageResult
- The result returned by the client for a sampling/createMessage request.
- DiscoverRequest
-
Requests the server's capability advertisement out-of-band, replacing
the former
initializehandshake now that protocol negotiation happens per-request via RequestMetaObject. - DiscoverResult
-
The server's capability advertisement, servers implementing this
protocol version MUST support
server/discover. - DiscoverResultResponse
- A successful response from the server for a server/discover request.
- ElicitRequest
- A request from the server to elicit additional information from the user via the client.
- ElicitRequestFormParams
- The parameters for a request to elicit non-sensitive information from the user via a form in the client.
- ElicitRequestFormParamsSchema
-
The MCP
ElicitRequestFormParamsSchemaschema type. - ElicitRequestParams
- Discriminated union of the two ElicitRequest param shapes, dispatched on ElicitRequestFormParams.mode / ElicitRequestURLParams.mode: a form-based elicitation, or a URL-based one.
- ElicitRequestURLParams
- The parameters for a request to elicit information from the user via a URL in the client.
- ElicitResult
- The result returned by the client for an elicitation/create request.
- EmbeddedResource
- An MCP resource embedded inside a prompt or tool-call result.
- EmptyResult
- A successful result that carries no data.
-
EnumSchema<
T> -
The MCP
EnumSchemaschema type. - Error
- A JSON-RPC 2.0 error object.
- GetPromptRequest
- Used by the client to get a prompt provided by the server.
- GetPromptRequestParams
- Parameters for a prompts/get request.
- GetPromptResult
- The result returned by the server for a prompts/get request.
- GetPromptResultOutcome
-
Discriminated union: either an InputRequiredResult pause or the
completed GetPromptResult, as returned by
GetPromptResultResponse.result. - GetPromptResultResponse
- A successful response from the server for a prompts/get request.
- HeaderMismatchError
-
Returned when a server rejects a request because HTTP header values do
not match the corresponding values in the request body, or required
headers are missing/malformed. For HTTP, the response status MUST be
400 Bad Request. - Icon
- An optionally-sized icon that may be displayed in a UI.
- ImageContent
- Image content block for LLM interactions.
- Implementation
- Describes an MCP client or server implementation.
- InputRequiredResult
- A result indicating the original request requires additional client input before the server can produce a final answer.
- InputResponseRequestParams
- Base params shape for requests that may resume a paused multi-round-trip operation by supplying inputResponses and/or requestState.
- InternalError
- JSON-RPC internal error (code -32603).
- InvalidParamsError
- JSON-RPC invalid params error (code -32602).
- InvalidRequestError
- JSON-RPC invalid request error (code -32600).
- JSONRPCErrorResponse
- A JSON-RPC 2.0 error response.
- JSONRPCMessage
- Union base for all JSON-RPC wire objects.
- JSONRPCNotification
- A JSON-RPC 2.0 notification (a request with no expected response).
- JSONRPCRequest
- A JSON-RPC 2.0 request that expects a response.
- JSONRPCResponse
- Abstract base for all JSON-RPC response objects.
- JSONRPCResultResponse
- A successful JSON-RPC 2.0 response carrying a Result.
- LegacyTitledEnumSchema
- Use TitledSingleSelectEnumSchema instead.
- ListPromptsRequest
- Sent from the client to request a list of prompts and prompt templates the server has.
- ListPromptsResult
- The result returned by the server for a prompts/list request.
- ListPromptsResultResponse
- A successful response from the server for a prompts/list request.
- ListResourcesRequest
- Sent from the client to request a list of resources the server has.
- ListResourcesResult
- The result returned by the server for a resources/list request.
- ListResourcesResultResponse
- A successful response from the server for a resources/list request.
- ListResourceTemplatesRequest
- Sent from the client to request a list of resource templates the server has.
- ListResourceTemplatesResult
- The result returned by the server for a resources/templates/list request.
- ListResourceTemplatesResultResponse
- A successful response from the server for a resources/templates/list request.
- ListRootsRequest
- Sent from the server to request a list of root URIs from the client.
- ListRootsResult
- The result returned by the client for a roots/list request.
- ListToolsRequest
- Sent from the client to request a list of tools the server has.
- ListToolsResult
- The result returned by the server for a tools/list request.
- ListToolsResultResponse
- A successful response from the server for a tools/list request.
- LoggingMessageNotification
- JSONRPCNotification of a log message passed from server to client.
- LoggingMessageNotificationParams
- Parameters for a notifications/message notification.
-
MapMC<
K, V> -
A
MapModelthat also satisfies MCP. - MCP
- Base interface for all MCP model objects.
- McpBuilder
- Declarative MCP capability builder.
- MetaObject
-
Holds the
_metamap present on many MCP types. - MethodNotFoundError
- JSON-RPC method not found error (code -32601).
- MissingRequiredClientCapabilityError
- Returned when a request omits a client capability the server requires for the requested operation.
- ModelHint
- Hints to use for model selection.
- ModelPreferences
- The server's preferences for model selection, requested of the client during sampling.
-
MultiSelectEnumSchema<
T> -
The MCP
MultiSelectEnumSchemaschema type. - NotificationMetaObject
-
The
_metaobject carried inside notification params. - NotificationParams
- Parameters shared by MCP notifications.
- NumberSchema
-
The MCP
NumberSchemaschema type. - PaginatedRequestParams
- Request params for paginated MCP list calls.
- ParseError
- JSON-RPC parse error (code -32700).
-
PrimitiveSchemaDefinition<
T> - Restricted schema definitions that only allow primitive types without nested objects or arrays.
- ProgressNotification
- An out-of-band notification used to inform the receiver of a progress update for a long-running request.
- ProgressNotificationParams
- Parameters for a notifications/progress notification.
- Prompt
- A prompt or prompt template offered by the server.
- PromptArgument
- Describes an argument accepted by a Prompt.
- PromptListChangedNotification
- An optional notification from the server to the client, informing it that the list of prompts it offers has changed.
- PromptMessage
- Describes a message returned as part of a prompt.
- PromptReference
- Identifies a prompt.
- ReadResourceRequest
- Sent from the client to the server, to read a specific resource URI.
- ReadResourceRequestParams
- Parameters for a resources/read request.
- ReadResourceResult
- The result returned by the server for a resources/read request.
- ReadResourceResultOutcome
-
Discriminated union: either an InputRequiredResult pause or the
completed ReadResourceResult, as returned by
ReadResourceResultResponse.result. - ReadResourceResultResponse
- A successful response from the server for a resources/read request.
- Reference
-
Discriminated union of completion reference targets: either a
PromptReference (
type: "ref/prompt") or a ResourceTemplateReference (type: "ref/resource"). - RequestMetaObject
-
The
_metaobject carried inside request params. - RequestParams
- Common params for any request.
- Resource
- A known resource that the server can serve.
- ResourceContents
- Base interface for resource content (text or blob).
- ResourceLink
- A resource link returned by a tool or included in a prompt.
- ResourceListChangedNotification
- An optional notification from the server to the client, informing it that the list of resources it can read from has changed.
- ResourceTemplate
- A URI template (RFC 6570) describing a family of resources.
- ResourceTemplateReference
- A reference to a resource or resource template definition.
- ResourceUpdatedNotification
- A notification from the server to the client, informing it that a resource has changed and may need to be read again.
- ResourceUpdatedNotificationParams
- Parameters for a notifications/resources/updated notification.
- Result
- Generic MCP result that may carry arbitrary extra fields.
- ResultMetaObject
-
The
_metaobject carried inside a Result. - Root
- Represents a root directory or file that the server can operate on.
- RootsListChangedNotification
-
A JSON-RPC notification for the
rootsListChangedevent. - SamplingMessage
- Describes a message issued to or received from an LLM API.
- SamplingMessageContentBlock
-
The MCP
SamplingMessageContentBlockschema type. -
Schema<
T> -
The MCP
Schemaschema type. - ServerCapabilities
- Capabilities declared by the MCP server.
-
SingleSelectEnumSchema<
T> -
The MCP
SingleSelectEnumSchemaschema type. - StringSchema
-
The MCP
StringSchemaschema type. - SubscriptionFilter
-
Filter describing which change notifications a
subscriptions/listenstream should deliver. - SubscriptionsAcknowledgedNotification
- Sent by the server to acknowledge that a subscriptions/listen subscription has been established and to report which notification types it agreed to honor.
- SubscriptionsAcknowledgedNotificationParams
-
The first message a server sends after a client opens a new
subscriptions/listenstream, acknowledging which notifications it will deliver on it. - SubscriptionsListenRequest
-
Opens a long-lived stream on which the server pushes change
notifications, replacing the former
resources/subscribe/resources/unsubscribeRPCs. - SubscriptionsListenRequestParams
- Parameters for a subscriptions/listen request.
- SubscriptionsListenResult
-
Sent by the server, at most once, to gracefully terminate a
subscriptions/listenstream. The result body is otherwise empty. - SubscriptionsListenResultMetaObject
-
The
_metaobject carried on a SubscriptionsListenResult. - SubscriptionsListenResultResponse
- A successful response from the server for a subscriptions/listen request, sent when the server tears the subscription down gracefully.
- TextContent
- Plain-text content for LLM interactions.
- TextResourceContents
- UTF-8 text resource contents.
- TitledMultiSelectEnumSchema
- Schema for multiple-selection enumeration with display titles for each option.
- TitledSingleSelectEnumSchema
- Schema for single-selection enumeration with display titles for each option.
- Tool
- A tool that the server exposes for the client to call.
- ToolAnnotations
- Behavioural hints for a Tool (all properties are advisory).
- ToolChoice
- Controls tool selection behavior for sampling requests.
- ToolListChangedNotification
- An optional notification from the server to the client, informing it that the list of tools it offers has changed.
- ToolResultContent
- The result of a tool use, provided by the user back to the assistant.
- ToolSchema
- Execution-related properties for a Tool. JSON Schema (2020-12) object used for a tool's Tool.inputSchema or Tool.outputSchema.
- ToolUseContent
- A request from the assistant to call a tool.
- UnsupportedProtocolVersionError
-
Returned when a server does not support the protocol version requested
via
RequestMetaObject["io.modelcontextprotocol/protocolVersion"]. - UntitledMultiSelectEnumSchema
- Schema for multiple-selection enumeration without display titles for options.
- UntitledSingleSelectEnumSchema
- Schema for single-selection enumeration without display titles for options.
Enums
- ActionType
- The user action in response to an elicitation request.
- CacheScope
-
Cache scope for a cacheable result (see DiscoverResult and the various
List*Result/ReadResourceResulttypes). - LoggingLevel
- The severity of a log message, mapped to syslog severities (RFC-5424).
- ResultType
- Indicates the type of a result, so a client knows how to parse it.
- Role
- The sender or recipient of messages and data in a conversation.
- StringFormat
-
The JSON Schema
formatkeyword for string-typed values. - Theme
- UI theme variants for Icon.
Typedefs
- InputRequests = dynamic
- InputResponses = dynamic
-
JSONObject
= Map<
String, Object?> - JSONValue = Object?
-
MethodHandler
= Future<
MCP> Function(Map<String, Object?> payload) -
PromptHandler
= Future<
GetPromptResult> Function(GetPromptRequest request) -
ResourceHandler
= Future<
ReadResourceResult> Function(ReadResourceRequest request) -
ToolHandler
= Future<
CallToolResult> Function(CallToolRequest request)