/**
 * Decision D8 (project/plans/migrator-launch-darkly.md §9.1): the `qfg migrate`
 * command's API-key flag is generalized from the launch-specific `--api-key` /
 * `LAUNCH_API_KEY` into a provider-agnostic `--source-api-key` /
 * `QUONFIG_MIGRATE_API_KEY`, with a per-provider env fallback. `--api-key` /
 * `LAUNCH_API_KEY` stay as deprecated aliases for the `launch` source.
 *
 * Precedence (highest first):
 *   1. `--source-api-key` flag   (oclif also fills it from QUONFIG_MIGRATE_API_KEY)
 *   2. `--api-key` flag          (oclif also fills it from LAUNCH_API_KEY; deprecated)
 *   3. per-provider env var      (LAUNCHDARKLY_API_KEY, FLAGSMITH_API_KEY, ...)
 */
/**
 * Per-provider env-var fallback, lowest precedence. Keyed by `--from` value so
 * every supported source has an obvious, source-named env var. `launch`'s entry
 * is redundant with the `--api-key` flag's own `env: LAUNCH_API_KEY` binding,
 * but is kept so the map is a complete record of every provider's env var.
 */
export declare const PROVIDER_API_KEY_ENV: Record<string, string>;
export interface SourceApiKeyInput {
    /** `--api-key` flag value (oclif also fills this from LAUNCH_API_KEY). Deprecated alias. */
    apiKeyFlag?: string;
    /** Process env, injectable for tests. Defaults to `process.env`. */
    env?: NodeJS.ProcessEnv;
    /** `--from` value — selects the per-provider env-var fallback. */
    from: string;
    /** `--source-api-key` flag value (oclif also fills this from QUONFIG_MIGRATE_API_KEY). */
    sourceApiKeyFlag?: string;
}
/** Resolve the source API key from flags + env, or `undefined` if none is configured. */
export declare function resolveSourceApiKey(input: SourceApiKeyInput): string | undefined;
/** One-line guidance for the "no key configured" error, naming every accepted input. */
export declare function missingSourceApiKeyMessage(from: string): string;