Module mcp 

MCP (Model Context Protocol) client — stdio and HTTP+SSE transport, JSON-RPC 2.0.

Supports the bounded subset needed for tool proxy:

• initialize / initialized handshake
• tools/list to discover tools
• tools/call to invoke them

Also supports:

• resources/list and resources/read
• prompts/list and prompts/get

Structs

ElicitationRequest

MCP elicitation request forwarded to a host (Claude elicitation control).

JsonRpcError

A JSON-RPC 2.0 error object.

JsonRpcRequest

A JSON-RPC 2.0 request.

JsonRpcResponse

A JSON-RPC 2.0 response.

McpClient

An MCP client owns a transport and manages JSON-RPC communication.

McpPrompt

A prompt template exposed by an MCP server.

McpPromptArgument

An argument to an MCP prompt template.

McpPromptMessage

A message in an MCP prompt response.

McpResource

A resource exposed by an MCP server.

McpResourceContent

Content returned from reading an MCP resource.

McpServer

Configuration for a single MCP server.

McpServerConfig

Configuration for a single MCP server in the Claude Code .mcp.json format.

McpTool

A tool that wraps an MCP server tool. Registered with a namespaced name mcp__<server_name>__<tool_name>.

McpToolAnnotations

Optional 2025-03-26 MCP tool annotations that carry hints about the tool’s side-effects. All fields default to false / None.

McpToolRouter

A mapping from tool name prefix to MCP server name.

McpToolSpec

A tool spec as returned by the MCP server’s tools/list.

ServerCapabilities

Capabilities advertised by an MCP server during the initialize handshake.

Enums

KillOutcome

Result of a graceful process kill.

McpServerTrust

Per-MCP-server trust level. Controls whether annotation hints from a server are believed when classifying side-effects.

Constants

DEFAULT_KILL_GRACE_PERIOD

Default grace period for MCP subprocess shutdown (5 seconds).

DEFAULT_STDIO_READ_TIMEOUT

Default timeout for reading a single JSON-RPC line from a stdio MCP server. Generous on purpose — real servers can pause briefly during large tool runs without being broken.

Traits

ElicitationHandler

Handles MCP -32042 UrlElicitationRequired by asking the host.

Functions

discover_mcp_servers

Discover MCP server configurations from the workspace.

dispatch_request

Dispatch a JSON-RPC request to the appropriate handler.

kill_gracefully

Kill a child process gracefully: send SIGTERM, wait for the grace period, then send SIGKILL if still alive.

load_mcp_config

Load MCP server configurations from a JSON file. Expected format:

new_elicitation_slot

Create an empty elicitation-handler slot.

Type Aliases

SharedElicitationHandler

Shared slot so the CLI control channel can install a handler after MCP clients are constructed.