/**
 * context.ts — Extract parent conversation context for subagent inheritance.
 */
import type { ExtensionContext } from "@earendil-works/pi-coding-agent";
/**
 * Extract plain text from a message content block array.
 *
 * Filters for objects with `type: "text"` and joins their `text` fields.
 * Non-text blocks (images, tool calls, etc.) are silently skipped.
 *
 * Single-pass loop instead of `.filter().map().join("\n")` — avoids
 * 3 intermediate array allocations per call. Called once per assistant
 * message in `buildParentContext`, so for a 200-message conversation
 * that's 200 × 3 = 600 fewer intermediate arrays.
 *
 * @param content - Array of message content blocks (typically from assistant messages)
 * @returns Concatenated text of all text blocks, joined by newlines
 */
export declare function extractText(content: unknown[]): string;
/**
 * Build a text representation of the parent conversation context.
 * Used when inherit_context is true to give the subagent visibility
 * into what has been discussed/done so far.
 */
export declare function buildParentContext(ctx: ExtensionContext): string;