Module mcp 

MCP (Model Context Protocol) integration. MCP (Model Context Protocol) integration.

Provides a built-in mcp tool that acts as a gateway to MCP servers, plus a per-tool direct-registration path (Phase 3) and a disk-backed metadata cache (Phase 1) that lets search / list / describe work without a live connection.

Architecture

McpTool (AgentTool) ──┐
McpDirectTool  (x N) ─┴─→ McpManager ─→ McpClient (per server, Transport-based)
                        │       ├── JSON-RPC over transport (stdio / http_sse)
                        │       ├── Metadata cache (disk-backed)
                        │       ├── Consent manager (disk-backed)
                        │       └── Lifecycle task (mpsc, owns idle/health timers)

Concurrency

McpManager is internally Arc<McpManager> after spawn(). The lifecycle timer task receives a Weak<McpManager> so it never participates in a reference cycle. The inner state is guarded by tokio::sync::Mutex for write paths and parking_lot::RwLock for cheap read paths (cache, consent).

Config format

{
  "mcpServers": {
    "my-server": {
      "command": "npx",
      "args": ["-y", "@my-org/mcp-server"],
      "lifecycle": "lazy",
      "idleTimeout": 10,
      "directTools": true
    }
  },
  "settings": {
    "toolPrefix": "server"
  }
}

Re-exports

pub use auth::Credential;

pub use auth::McpCredentialProvider;

pub use auth::NoopCredentialProvider;

pub use cache::MetadataCache;

pub use client::McpClient;

pub use client::McpLogLevel;

pub use client::McpPrompt;

pub use client::McpPromptArgument;

pub use client::McpSamplingRequest;

pub use consent::ConsentManager;

pub use direct_tool::McpDirectTool;

pub use error::McpError;

pub use spawn::NoopSpawnValidator;

pub use spawn::SpawnValidator;

pub use tool::McpTool;

pub use transport::McpTransport;

pub use transport::http::StreamableHttpTransport;

pub use transport::stdio::StdioTransport;

pub use types::ConsentState;

pub use types::DirectToolDef;

pub use types::DirectToolsConfig;

pub use types::LifecycleMode;

pub use types::McpCallResult;

pub use types::McpConfig;

pub use types::McpConnectionStatus;

pub use types::McpContent;

pub use types::McpDashboardData;

pub use types::McpServerInfo;

pub use types::McpSettings;

pub use types::McpSettingsView;

pub use types::McpToolDef;

pub use types::McpToolInfo;

pub use types::ServerEntry;

pub use types::ServerInfo;

pub use types::ServerStatus;

pub use types::ToolMetadata;

pub use types::ToolPrefix;

pub use types::effective_prefix_mode;

pub use types::format_schema;

pub use types::format_tool_name;

pub use types::get_server_prefix;

Modules

auth

MCP credential provider (v2.1).

cache

MCP tool metadata disk cache.

client

MCP JSON-RPC client.

config

MCP configuration loading.

consent

MCP consent management — two policies over one store.

content

MCP content transformation.

direct_tool

Direct MCP tool → AgentTool bridge (Phase 3).

error

Typed errors for MCP operations.

lifecycle

Channel-based MCP server lifecycle management.

spawn

MCP server spawn validation policy hook.

tool

MCP proxy tool.

transport

MCP transport layer abstraction.

types

Config format …

Structs

McpManager

Central manager for all MCP server connections.

McpManagerInner

Inner mutable state for McpManager.

Constants

DEFAULT_FAILURE_BACKOFF_SECS

Default back-off period after a server connection failure (seconds).

DEFAULT_IDLE_TIMEOUT_MINS

Default global idle timeout (minutes).