McpClient
Defined in: src/mcp.ts:89
MCP Client for interacting with Model Context Protocol servers.
Constructors
Section titled “Constructors”Constructor
Section titled “Constructor”new McpClient(args): McpClient;Defined in: src/mcp.ts:111
Parameters
Section titled “Parameters”| Parameter | Type |
|---|---|
args | McpClientConfig |
Returns
Section titled “Returns”McpClient
Properties
Section titled “Properties”DEFAULT_TTL
Section titled “DEFAULT_TTL”readonly static DEFAULT_TTL: 60000 = 60000;Defined in: src/mcp.ts:91
Default TTL for task polling in milliseconds (60 seconds).
DEFAULT_POLL_TIMEOUT
Section titled “DEFAULT_POLL_TIMEOUT”readonly static DEFAULT_POLL_TIMEOUT: 300000 = 300000;Defined in: src/mcp.ts:94
Default poll timeout for task completion in milliseconds (5 minutes).
Accessors
Section titled “Accessors”client
Section titled “client”Get Signature
Section titled “Get Signature”get client(): Client;Defined in: src/mcp.ts:146
Returns
Section titled “Returns”Client
serverCapabilities
Section titled “serverCapabilities”Get Signature
Section titled “Get Signature”get serverCapabilities(): any;Defined in: src/mcp.ts:150
Returns
Section titled “Returns”any
serverVersion
Section titled “serverVersion”Get Signature
Section titled “Get Signature”get serverVersion(): any;Defined in: src/mcp.ts:154
Returns
Section titled “Returns”any
serverInstructions
Section titled “serverInstructions”Get Signature
Section titled “Get Signature”get serverInstructions(): string;Defined in: src/mcp.ts:158
Returns
Section titled “Returns”string
connectionState
Section titled “connectionState”Get Signature
Section titled “Get Signature”get connectionState(): McpConnectionState;Defined in: src/mcp.ts:162
Returns
Section titled “Returns”onToolsChanged
Section titled “onToolsChanged”Set Signature
Section titled “Set Signature”set onToolsChanged(callback): void;Defined in: src/mcp.ts:264
Sets a callback invoked when the MCP server’s tool list changes at runtime.
Parameters
Section titled “Parameters”| Parameter | Type | Description |
|---|---|---|
callback | (oldTools, newTools) => void | Handler receiving the previous tool names and the refreshed tool instances, or undefined to remove the callback. |
Returns
Section titled “Returns”void
Methods
Section titled “Methods”connect()
Section titled “connect()”connect(reconnect?): Promise<void>;Defined in: src/mcp.ts:176
Connects the MCP client to the server.
Called lazily before any operation that requires a connection. When failOpen is true,
connection failures are swallowed and the client enters a 'failed' state — subsequent
calls are no-ops until connect(true) is called explicitly to retry.
Parameters
Section titled “Parameters”| Parameter | Type | Default value | Description |
|---|---|---|---|
reconnect | boolean | false | When true, forces a reconnect even if already connected or failed. |
Returns
Section titled “Returns”Promise<void>
A promise that resolves when the connection is established.
disconnect()
Section titled “disconnect()”disconnect(): Promise<void>;Defined in: src/mcp.ts:208
Disconnects the MCP client from the server and cleans up resources.
Returns
Section titled “Returns”Promise<void>
A promise that resolves when the disconnection is complete.
[asyncDispose]()
Section titled “[asyncDispose]()”asyncDispose: Promise<void>;Defined in: src/mcp.ts:219
Enables the await using pattern for automatic resource cleanup.
Delegates to McpClient.disconnect.
Returns
Section titled “Returns”Promise<void>
listTools()
Section titled “listTools()”listTools(): Promise<McpTool[]>;Defined in: src/mcp.ts:228
Lists the tools available on the server and returns them as executable McpTool instances.
Returns
Section titled “Returns”Promise<McpTool[]>
A promise that resolves with an array of McpTool instances.
callTool()
Section titled “callTool()”callTool(tool, args): Promise<JSONValue>;Defined in: src/mcp.ts:301
Invoke a tool on the connected MCP server using an McpTool instance.
When tasksConfig was provided to the client constructor, uses experimental
task-based invocation which supports long-running tools with progress tracking.
Otherwise, calls tools directly without task management.
Parameters
Section titled “Parameters”| Parameter | Type | Description |
|---|---|---|
tool | McpTool | The McpTool instance to invoke. |
args | JSONValue | The arguments to pass to the tool. |
Returns
Section titled “Returns”Promise<JSONValue>
A promise that resolves with the result of the tool invocation.