Exa

Exa is a neural search API built specifically for AI agents and applications. Where traditional keyword-based search engines return pages ranked by relevance signals like backlinks and click-through rates, Exa uses semantic understanding to find content that matches the meaning of a query — making it well-suited for powering autonomous agents that need precise, actionable web data rather than a list of links to skim.

The core product is a REST API with three main endpoints: Search (finding URLs across the web), Contents (extracting clean text from pages), and Answer (returning direct answers grounded in web sources). A fourth product, Websets, allows users to build structured datasets from web content — useful for monitoring, enrichment, and research pipelines.

Exa maintains specialized indexes across several verticals. For coding agents, it indexes millions of GitHub repositories, documentation sites, and Stack Overflow threads with high-accuracy code retrieval. For finance, it covers 70M+ companies with historical market data and news. For recruiting, it indexes 1B+ people and company profiles. This vertical specialization distinguishes it from general-purpose search APIs that apply a single index across all queries.

On the performance side, Exa benchmarks favorably against Perplexity and Brave on accuracy metrics including FRAMES, Tip-of-Tongue, and Seal0 — three retrieval benchmarks that test factual grounding and hard-to-find information. Its Exa Instant mode returns results in under 180ms, which matters for real-time agent workflows where latency compounds across multiple search calls.

In the broader ecosystem, Exa competes with Tavily, Brave Search API, Perplexity API, and Serper. Compared to these, Exa differentiates on semantic search quality and its specialized vertical indexes. Tavily is popular for lightweight agent integrations and is well-documented in LangChain/LlamaIndex ecosystems. Brave offers keyword-based search with privacy focus. Exa's positioning is explicitly toward production AI applications that need high recall on difficult queries, not casual or exploratory search.

The tool is used in production by Notion (for news agents), Cursor (for coding assistance), HubSpot (for company and people monitoring), Point72 (for financial intelligence), and a number of other enterprise customers. It also offers an MCP (Model Context Protocol) server, making it directly usable with Claude and other MCP-compatible AI assistants without custom integration work.

For developers building research agents, competitive intelligence tools, or any AI system that needs to retrieve specific facts from the web, Exa offers a more structured and semantically grounded alternative to wrapping a consumer search engine.