Engineering deep-dives, product updates, and lessons from building retrieval for AI agents.https://withcharcoal.com/https://withcharcoal.com/blog/deep_research_api/https://withcharcoal.com/blog/deep_research_api/Deep research APIs let AI agents iteratively search, reason, and synthesize across internal documents — going beyond basic RAG. Learn how they work, how they differ from web deep research, and when you need one.Mon, 06 Apr 2026 00:00:00 GMThttps://withcharcoal.com/blog/introducing_charcoal/https://withcharcoal.com/blog/introducing_charcoal/We raised $2.5M led by Mischief to build the retrieval API purpose-built for AI agents.Sun, 15 Feb 2026 00:00:00 GMT