serp.fast

AI Search API

An AI search API is a web service that lets applications query the internet and receive results optimized for consumption by large language models. Unlike traditional search APIs that return ranked lists of blue links, AI search APIs typically return cleaned text content, relevance-scored passages, and structured metadata – the kind of output you can feed directly into an LLM prompt or RAG pipeline without additional parsing.

The category emerged because LLMs need factual grounding but cannot browse the web themselves. An AI search API bridges that gap: your application sends a natural-language query, the API searches the web, retrieves and processes the top results, and returns content that is ready to be injected into a model's context window. Some providers, like Exa, use embeddings-based retrieval to find semantically relevant pages rather than relying on keyword matching. Others, like Tavily, focus on real-time search with built-in content extraction tuned for agent workflows.

For product builders, the key evaluation criteria are result quality (does the API surface genuinely relevant sources?), content extraction depth (do you get full-page text or just snippets?), latency (can it serve an agent that needs answers in under two seconds?), and cost per query at scale. Most AI search APIs price per query in the range of $1–10 per thousand calls, which can become a significant line item for high-volume agent products.

The market is moving fast. Exa reached roughly $10M ARR with embeddings-based search. Tavily was acquired by Nebius Group. Brave Search API offers an independent index of 40 billion pages with no upstream dependency on Google. Perplexity's Sonar API packages its answer engine as an API. Each makes different tradeoffs between independence, depth, speed, and price – and the right choice depends on whether you are building a research assistant, a customer-facing chatbot, or an autonomous agent that needs to verify facts before acting.

Tools that handle ai search api

4 tools in the serp.fast directory are commonly used for ai search api workflows, spanning ai-native search apis, independent web indexes. Each is reviewed independently with pricing and editorial assessment.

Exa

Neural search engine using embeddings-based next-link prediction – finds semantically similar content, not just keyword matches.

Freemium
Tavily

Real-time search API purpose-built for AI agents and RAG pipelines, now owned by Nebius Group.

Freemium
Perplexity Sonar

LLM-powered search API with built-in citations, offering multi-tier model options from fast to deep research.

Paid
Brave Search API

Programmatic access to the only independent Western search index at scale – 40B+ pages, adding 100M+ new pages daily.

Freemium

Browse by category

AI-Native Search APIs Search APIs built specifically for LLMs and AI agents. Return structured, embedding-ready results instead of raw HTML.
Independent Web Indexes Their own crawl of the web. Not Google, not Bing – independent search indexes you can query via API.