@tanstack/ai/dist/esm/activities/chat/middleware/load-child.d.ts

Type-safe TypeScript AI SDK for streaming chat, tool calling, agents, structured outputs, and multimodal generation.

import { ModelMessage, UIMessage } from '../../../types.js';
/**
 * Loads the stored transcript of a finished subagent run by its
 * `subagentRunId`. Returns `undefined` for an unknown id. A persistence
 * middleware provides it. The agent tools read it to continue a
 * child by `sessionId`. When `agent` is set, only that agent can continue
 * the child. A middleware that provides it must list `LoadChildCapability`
 * in `provides`. Only then do the agent tools take `sessionId`.
 *
 * With `parentSubagentRunId`, it loads a nested child: a child that the child
 * `parentSubagentRunId` started. It returns `undefined` when that child did
 * not start it. A loader that ignores the option fails closed for nested
 * children.
 */
export type LoadChild = (subagentRunId: string, options?: {
    parentSubagentRunId?: string;
}) => Promise<{
    messages: Array<ModelMessage | UIMessage>;
    /** The name of the agent the child ran under. */
    agent?: string;
    /**
     * While the child waits on an interrupt: the stored messages of the call
     * that waits. A resume of that child continues from these, not from the
     * messages on the card that the client sent back. Without it, the agent
     * tool does not resume the child.
     */
    pending?: Array<ModelMessage | UIMessage>;
    /** While the child waits: the ids of the interrupts it waits on. */
    interruptIds?: Array<string>;
    /** The tool call of the parent that started the child, if any. */
    parentToolCallId?: string;
} | undefined>;
export declare const LoadChildCapability: import('./capabilities.js').Capability<LoadChild, "load-child">;
export declare const getLoadChild: import('./capabilities.js').CapabilityGetter<LoadChild>, provideLoadChild: import('./capabilities.js').CapabilityProvider<LoadChild>;