Does the description explain when to use this tool, when not to, or what alternatives exist?
Opens with an explicit trigger ('USE WHEN starting disease research or a swarm'), gives a parameter-level usage rule (pass swarm=N for a deterministic split), an explicit anti-pattern (never sum per-domain counts), and a NEXT chain (get_disease_dossier, then lanes in parallel, then submit_finding). Alternatives and exclusions are stated rather than inferred.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.