Best Search MCP servers for AI agents.

Web search is the headline act. exa offers fast, intelligence-ranked web search and crawling (plus Exa-code, a context tool for coding questions), tavily-mcp is built specifically for LLM consumption with cleaned, relevant extracts, and brightdata-mcp brings Bright Data's unblocking infrastructure so agents can search and navigate pages that resist ordinary fetching.

Code search is its own discipline: Serena MCP provides semantic retrieval and editing over a codebase — closer to an IDE for your agent than a search box — and socraticode indexes local codebases for semantic search and dependency graphs. Academic search has a clear leader in arxiv-mcp-server: paper search, full-text download, semantic search, and citation graphs. And data exploration rounds it out — Metabase, the most-starred server in this category, lets agents search, query, and visualize data inside a Metabase instance.

Match the index to the question. General web servers like exa and tavily-mcp answer 'what does the world know' questions; they differ on result shape (snippets vs full cleaned content) and ranking philosophy, so test both against your actual queries. If your agent hits sites with anti-bot protection, that's brightdata-mcp's specific territory. If the corpus is your own code or papers, the specialists (Serena, socraticode, arxiv-mcp-server) beat any general engine.

Then look at result economics. Search results are pasted into your model's context on every call, so a server returning ten clean, deduplicated extracts is cheaper and more accurate in practice than one returning raw HTML. The LLM-first engines were designed around exactly this constraint.

Humans issue one query and click around. Agents issue bursts — reformulating the same question five ways, fanning out across subtopics, then synthesizing. That access pattern punishes per-seat or monthly-quota pricing and rewards APIs that are fast, parallel-friendly, and priced per call. It's also why hosted search is the most natural x402 category in the index: each query has a real marginal cost to the provider and a clear value to the agent.

A hosted search endpoint claimed on Loomal can price each query in USDC from $0.01, with the agent paying automatically via the HTTP 402 flow before the handler runs — no API key signup standing between an agent and its first query.

With this much depth, the index signals matter: stars indicate adoption, claimed listings mean the maintainer has verified ownership and published a live tool list, and configured pricing tells you the endpoint is run as a service rather than a side project. Filter the marketplace by the Search category and sort from there — and check the per-server pages for the live-probed tool lists before wiring anything into production.