/**
 * formatFacts — render loaded `Fact` entries into a single system
 * message for prompt injection.
 *
 * Reads from scope:  `loadedFacts`
 * Writes to scope:   `formatted` (Message[] — one system message, or empty)
 *
 * Facts are tiny and semantically distinct from beats/messages, so they
 * render as a compact key/value block rather than a narrative paragraph
 * or per-entry `<memory>` tags. The default shape:
 *
 *   Known facts about the user:
 *
 *   - user.name: Alice
 *   - user.email: alice@example.com
 *   - user.preferences.color: blue
 *
 * Why one block, not one message per fact?
 *   LLMs parse key/value lists efficiently; splitting would waste
 *   tokens on per-message system overhead and break up the list's
 *   visual grouping.
 *
 * Why NOT run facts through `pickByBudget`?
 *   Facts are typically 10-50 items, each a handful of tokens. Picking
 *   subsets is rarely useful — the user either knows your name or
 *   they don't. Consumers who *do* want budget-based fact pruning can
 *   copy-paste this stage and wrap it with a picker.
 */
import type { TypedScope } from 'footprintjs';
import type { MemoryEntry } from '../entry/index.js';
import type { Fact } from './types.js';
import type { FactPipelineState } from './extractFacts.js';
export interface FormatFactsConfig {
    /**
     * Header prepended to the injected message. Explains to the LLM what
     * follows and what it's for. Override if your app has specific
     * phrasing guidance.
     */
    readonly header?: string;
    /** Footer appended after the fact list. Empty by default. */
    readonly footer?: string;
    /**
     * When `true`, appends `(conf 0.xx)` after each fact's value. Off by
     * default — confidence is usually noise for the LLM and only useful
     * in audit / debug flows.
     */
    readonly showConfidence?: boolean;
    /**
     * Custom per-fact renderer. Receives the entry; returns the block
     * string (without the leading `- ` bullet). Use for app-specific
     * formatting: custom attribution, hiding category info, etc.
     */
    readonly renderFact?: (entry: MemoryEntry<Fact>) => string;
    /**
     * Inject the message even when `loadedFacts` is empty. Usually
     * undesired — an empty list is noise. Off by default.
     */
    readonly emitWhenEmpty?: boolean;
}
export declare function formatFacts(config?: FormatFactsConfig): (scope: TypedScope<FactPipelineState>) => Promise<void>;