> For the complete documentation index, see [llms.txt](https://docs.wellcomecollection.org/catalogue-api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.wellcomecollection.org/catalogue-api/search.md).

# Search

These docs describe the development of our search engine and the systems we've used to test it.

## The story so far

We began with a [data-informed approach](https://github.com/wellcomecollection/catalogue-api/blob/main/docs/search/data_informed/README.md) to measuring relevance, running candidate queries against each other in AB tests, and taking incremental steps based on some illustrative metrics. After a few months of development, we found that this approach was insufficient to drive the development of new features safely or reliably. Most of this documentation is now outdated as a result.

Instead, we started developing [rank](/catalogue-api/search/rank.md), a system which uses known examples of tricky search-term / document pairs to constrain the query. Rank is the system we use to develop queries and mappings today.

## Current queries

You can read an explanation of the current queries' structure [here](/catalogue-api/search/current_queries.md).