Function selectBackend

src/tools/web/web-search.ts:16–33

(name: string | undefined)

/** Build a backend instance from a string id. Defaults to duckduckgo on unknown values. */
export function selectBackend(name: string | undefined): WebSearchBackend {
  switch ((name ?? 'duckduckgo').toLowerCase()) {
    case 'tavily':
      return new TavilyBackend();
    case 'brave':
      return new BraveBackend();
    case 'firecrawl':
    case 'fc':
      return new FirecrawlBackend();
    case 'duckduckgo':
    case 'ddg':
    case undefined:
      return new DuckDuckGoBackend();
    default:
      logger.warn(`Unknown web_search backend '${name}', falling back to duckduckgo`);
      return new DuckDuckGoBackend();
  }
}

/**
 * Build the fallback chain. If the primary backend fails or returns nothing,