/**
 * defineSteering — sugar for always-on system-prompt Injections.
 *
 * Steering docs are the simplest form of context engineering: a fixed
 * piece of guidance the LLM should follow on every iteration. Style
 * guides, output format rules, persona statements, safety policies.
 *
 * Produces an `Injection` with:
 *   - flavor: `'steering'`
 *   - trigger: `{ kind: 'always' }`
 *   - inject: `{ systemPrompt: prompt }`
 *
 * @example
 *   const jsonOnly = defineSteering({
 *     id: 'json-only',
 *     description: 'Always respond with valid JSON.',
 *     prompt: 'Respond with JSON only. No prose. No markdown.',
 *   });
 */
import type { Injection } from '../types.js';
import type { CachePolicy } from '../../../cache/types.js';
export interface DefineSteeringOptions {
    readonly id: string;
    readonly description?: string;
    /** Always-on text appended to the system-prompt slot. */
    readonly prompt: string;
    /**
     * Cache policy for this steering injection. Defaults to `'always'`
     * — steering is by definition always-on stable content, ideal for
     * provider-side caching. Override with `'never'` if the prompt
     * contains volatile content (timestamps, per-request IDs).
     *
     * See `CachePolicy` in `agentfootprint/src/cache/types.ts` for all
     * variants. The CacheDecision subflow reads this from
     * `injection.metadata.cache` each iteration.
     */
    readonly cache?: CachePolicy;
}
export declare function defineSteering(opts: DefineSteeringOptions): Injection;