McpClient
Defined in: src/mcp/client.ts:154
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/client.ts:194
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/client.ts:156
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/client.ts:159
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/client.ts:265
Returns
Section titled “Returns”Client
serverCapabilities
Section titled “serverCapabilities”Get Signature
Section titled “Get Signature”get serverCapabilities(): any;Defined in: src/mcp/client.ts:269
Returns
Section titled “Returns”any
serverVersion
Section titled “serverVersion”Get Signature
Section titled “Get Signature”get serverVersion(): any;Defined in: src/mcp/client.ts:273
Returns
Section titled “Returns”any
serverInstructions
Section titled “serverInstructions”Get Signature
Section titled “Get Signature”get serverInstructions(): string;Defined in: src/mcp/client.ts:277
Returns
Section titled “Returns”string
connectionState
Section titled “connectionState”Get Signature
Section titled “Get Signature”get connectionState(): McpConnectionState;Defined in: src/mcp/client.ts:281
Returns
Section titled “Returns”clientName
Section titled “clientName”Get Signature
Section titled “Get Signature”get clientName(): string;Defined in: src/mcp/client.ts:285
Returns
Section titled “Returns”string
continueOnError
Section titled “continueOnError”Get Signature
Section titled “Get Signature”get continueOnError(): boolean;Defined in: src/mcp/client.ts:289
Returns
Section titled “Returns”boolean
onToolsChanged
Section titled “onToolsChanged”Set Signature
Section titled “Set Signature”set onToolsChanged(callback): void;Defined in: src/mcp/client.ts:408
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”loadServers()
Section titled “loadServers()”static loadServers(config, defaults?): Promise<McpClient[]>;Defined in: src/mcp/client.ts:168
Parses an MCP servers config (file path or object) and returns McpClient instances.
Parameters
Section titled “Parameters”| Parameter | Type | Description |
|---|---|---|
config | | string | Record<string, McpServerConfig> | A file path to a JSON config, or a flat server map object. |
defaults? | McpClientOptions | Options applied to all clients unless overridden per-server. |
Returns
Section titled “Returns”Promise<McpClient[]>
An array of McpClient instances ready to be passed to an Agent.
connect()
Section titled “connect()”connect(reconnect?): Promise<void>;Defined in: src/mcp/client.ts:303
Connects the MCP client to the server.
Called lazily before any operation that requires a connection. When continueOnError 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/client.ts:335
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/client.ts:346
Enables the await using pattern for automatic resource cleanup.
Delegates to McpClient.disconnect.
Returns
Section titled “Returns”Promise<void>
listTools()
Section titled “listTools()”listTools(options?): Promise<McpTool[]>;Defined in: src/mcp/client.ts:360
Lists the tools available on the server and returns them as executable McpTool instances.
A prefix renames tools for the agent only; tools are always invoked, and matched by string and
RegExp filters, under their server-side name.
Parameters
Section titled “Parameters”| Parameter | Type | Description |
|---|---|---|
options? | McpListToolsOptions | Overrides for the prefix and filters set on the client. An omitted field uses the client’s value; an explicit empty string or empty object disables it. |
Returns
Section titled “Returns”Promise<McpTool[]>
A promise that resolves with an array of McpTool instances.
callTool()
Section titled “callTool()”callTool( tool, args,options?): Promise<JSONValue>;Defined in: src/mcp/client.ts:446
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. |
options? | McpCallToolOptions | Optional settings for the request. |
Returns
Section titled “Returns”Promise<JSONValue>
A promise that resolves with the result of the tool invocation.