How to write a Claude tool description that actually works.
This site is a focused catalog of prompt-engineering best practices specific to writing tool and function descriptions and schemas -- clarity, structure, examples inside the description, parameter naming, explicit scoping of when (and when not) to use a tool. It deliberately does not duplicate subagentprompts.com's broader 14-technique general prompting catalog; this is the tool-description-specific subset, cross-linked rather than repeated.
Every row is specifically about tool/function description writing, not prompting in general -- see subagentprompts.com for the broader catalog.
Every practice pairs a concrete good example against a concrete bad one, following its own advice about embedding examples.
Practices reflect Anthropic's own well-established published tool-use guidance and general best practice, several cross-referenced against this repo's own real tool/skill descriptions.
Live catalog
All rows are seeded from established prompt-engineering guidance for tool/function descriptions. Browse by category → or hit the JSON API.