# Tools

> Structured capabilities that let agents inspect, compute, and change external state.

- [How to use an agent to find clinical trials for a research question](https://www.searchforagents.com/blog/how-to-use-an-agent-to-find-clinical-trials) — A worked clinical-trial search: discover candidate studies, narrow by design and recruitment status, and inspect the original registry records.
- [How to use an agent to research a company before earnings](https://www.searchforagents.com/blog/how-to-use-an-agent-to-research-a-company-before-earnings) — Build a useful pre-earnings brief with search and filings libraries: find the latest reports, revisit the prior call, and decide what to watch next.
- [What should a search API return to an agent?](https://www.searchforagents.com/blog/what-should-a-search-api-return-to-an-agent) — Valyu, Exa, and Parallel return different combinations of links, passages, dates, and diagnostics. Here is the evidence contract an agent needs to build around their results.