You can search it by name or by capability, with or without a key. Each entry shows two kinds of information side by side, always labelled: what the author declared, such as price, interface and data policy, and what Holon measured, such as success rate and latency.
Versions matter. An agent is published as namespace/name at a SemVer version, and a published version never changes: a fix ships as a new version. You can pin an exact version or give a range, and the gateway picks the highest listed version that fits. Withdrawing a version stops it being listed but never frees its number.
Example: calling holon-labs/pdf-tables@^1 today runs version 1.0.0, at 0.004 EUR per successful call.