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McpClient

Defined in: src/mcp.ts:89

MCP Client for interacting with Model Context Protocol servers.

new McpClient(args): McpClient;

Defined in: src/mcp.ts:107

ParameterType
argsMcpClientConfig

McpClient

readonly static DEFAULT_TTL: 60000 = 60000;

Defined in: src/mcp.ts:91

Default TTL for task polling in milliseconds (60 seconds).


readonly static DEFAULT_POLL_TIMEOUT: 300000 = 300000;

Defined in: src/mcp.ts:94

Default poll timeout for task completion in milliseconds (5 minutes).

get client(): Client;

Defined in: src/mcp.ts:131

Client


get serverCapabilities(): any;

Defined in: src/mcp.ts:135

any


get serverVersion(): any;

Defined in: src/mcp.ts:139

any


get serverInstructions(): string;

Defined in: src/mcp.ts:143

string


get connectionState(): McpConnectionState;

Defined in: src/mcp.ts:147

McpConnectionState

connect(reconnect?): Promise<void>;

Defined in: src/mcp.ts:161

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.

ParameterTypeDefault valueDescription
reconnectbooleanfalseWhen true, forces a reconnect even if already connected or failed.

Promise<void>

A promise that resolves when the connection is established.


disconnect(): Promise<void>;

Defined in: src/mcp.ts:193

Disconnects the MCP client from the server and cleans up resources.

Promise<void>

A promise that resolves when the disconnection is complete.


asyncDispose: Promise<void>;

Defined in: src/mcp.ts:204

Enables the await using pattern for automatic resource cleanup. Delegates to McpClient.disconnect.

Promise<void>


listTools(): Promise<McpTool[]>;

Defined in: src/mcp.ts:213

Lists the tools available on the server and returns them as executable McpTool instances.

Promise<McpTool[]>

A promise that resolves with an array of McpTool instances.


callTool(tool, args): Promise<JSONValue>;

Defined in: src/mcp.ts:252

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.

ParameterTypeDescription
toolMcpToolThe McpTool instance to invoke.
argsJSONValueThe arguments to pass to the tool.

Promise<JSONValue>

A promise that resolves with the result of the tool invocation.