help: invalid_spec

What it means: The kind rejected the spec's shape -- a required field missing, or a field that doesn't parse the way that kind expects.

Likely cause: See data.field/data.expected in the payload: it names exactly which field and what was expected, in the same "<field>: <expected>" convention every kind uses.

Fix: Fix the named field (data.example in the payload, when present, is a working value for it) and republish, or dry-run first with host.tool_publish(..., dry_run: true).

See also: docs/agent-quickstart.md#quickstart-for-agents