Best Retrieval-Augmented Generation (RAG) Software for Claude Code

Keenable gives AI agents live web search from an index it crawls and ranks itself: 100B+ documents, under 250ms p95 in US East. Agents get two tools: search_web_pages returns ranked results with title, URL and snippet, filtered by publish date, crawl date or site. fetch_page_content returns any page as clean markdown. One API key covers the REST API, the MCP server and the CLI for macOS, Linux and Windows. Integrations include LangChain, LlamaIndex, Haystack, Mastra, Vercel AI SDK and NVIDIA NeMo Agent Toolkit. Quality is measured in public on NEEDLE, a benchmark rerun daily across search providers against an oracle ranking pooled from their results. AI labs and inference platforms can move to dedicated capacity from $1 per 1,000 requests at 100 RPS, in the cloud or on-premises. Time Machine, in early access, rewinds both the corpus and the ranking to a past moment with one parameter, query_time.