@tanstack/ai-mcp/dist/esm/apps/session-store.d.ts

Host-side Model Context Protocol client for TanStack AI: discover and run MCP server tools, resources, and prompts in any adapter's chat() loop, with generated end-to-end types.

import { ClientOptions } from '@modelcontextprotocol/sdk/client/index.js';
import { TransportConfig } from '../transport.js';
export interface McpServerDescriptor {
    /**
     * The serializable connection config the call handler reconnects from.
     * `undefined` for a client built from a ready-made `Transport` instance
     * (single-use, not reconnectable) — the handler rejects such a call with a
     * clear error.
     */
    transport: TransportConfig | undefined;
    prefix?: string;
    /**
     * Options to rebuild the client with. Carried so a reconnect keeps a custom
     * `jsonSchemaValidator` — an edge runtime cannot use the SDK's AJV default.
     */
    clientOptions?: ClientOptions;
}
export interface McpSessionStore {
    /**
     * Resolve the server descriptor for a thread+serverId, or null if unknown.
     *
     * `serverId` may be undefined when the widget omits it (single-server setups);
     * implementations should default to the sole recorded server in that case.
     */
    get: (threadId: string, serverId: string | undefined) => Promise<McpServerDescriptor | null>;
    /** Record the servers a thread may interact with (called from the chat route). */
    set: (threadId: string, servers: Record<string, McpServerDescriptor>) => Promise<void>;
}
/** Call-handler request shape; imported by call-handler.ts from this module. */
export interface McpAppCallRequest {
    threadId: string;
    /**
     * The server the widget targets. May be undefined when the widget omits it
     * (single-server setups) — the handler defaults to the sole configured server.
     */
    serverId?: string;
    toolName: string;
    args?: unknown;
    /**
     * Reserved — forwarded by the bridge for correlation purposes but not
     * consumed by the call handler. Mirrors the `meta` convention: accepted
     * on the wire, carried through, but the handler does not read it.
     */
    messageId?: string;
}
/**
 * Creates a simple in-memory McpSessionStore.
 *
 * TTL is enforced on read (prune-on-read) and slides on each successful hit —
 * this is single-instance only. The `McpSessionStore` interface is the
 * extension point for persistent/SQL backends, which can drop in later with no
 * API change.
 *
 * Growth is bounded by an opportunistic sweep on `set()`: prune-on-read alone
 * never reclaims a thread that is recorded but never has a widget interaction
 * (the common case — most threads never touch a `ui://` widget), so without the
 * sweep the map would grow by one entry per chat thread for the process
 * lifetime. The sweep drops every entry older than the TTL whenever a new one is
 * written, keeping the map bounded to threads active within the TTL window.
 */
export declare function inMemoryMcpSessionStore(opts?: {
    ttlMs?: number;
}): McpSessionStore;