probe
The engine serves a consuming skill's SKILL.md and references/ over MCP, because most hosts carry neither into the model's context on their own. This payload exists so that behaviour can be tested without borrowing a real skill's documentation — webindex ships no SKILL.md of its own, being an engine rather than a skill.
Body long enough to be a plausible document, so the description extractor has real prose to pull its first paragraph from rather than a title.