Exa (88/100) and Tavily (87/100) both let agents sign up with an email address, get an API key, and run a search in under 5 minutes. No phone verification, no CAPTCHA, no human review.

That sounds like table stakes. It isn't.

Exa — 88/100 The only search API with both an MCP server and agent-native account creation. Semantic search returns structured data: title, author, date, full text highlights. You don't get a blob of HTML and a link — you get what you actually need. Free tier: 1,000 searches/month, no domain verification required. The one gap: no llms.txt, so agents discovering Exa cold have to infer the API shape from docs rather than a machine-readable summary.

Tavily — 87/100 Purpose-built for agentic research. The differentiator is depth control: you can ask for a "basic" sweep or a "deep" crawl depending on whether you need quick facts or thorough research. Returns clean JSON by default. Also has an MCP server. Used in LangChain and AutoGPT integrations — which means the library of examples is already there. Same gap as Exa: no llms.txt.

One data insight from rating these two alongside the rest:

Exa and Tavily were founded by people who expected agents to be the primary user. You can tell by the fact that "can an agent sign up without help?" wasn't an afterthought — it's just the default. Every other search API we've rated (Google Custom Search, Bing Search, Algolia) required some combination of phone verification, project creation UI, or manual API key approval. The gap between agent-native and agent-compatible is roughly 20 points on our scale. It shows up most clearly in search, because search is one of the most common agent tasks.

If you're building an agent that needs to look things up, start with Exa or Tavily. Both work. Both have MCP servers. The full scores are at agentnativeregistry.com.

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