SKM-D02 · Error
`description` is longer than 1024 characters
The specification caps `description` at 1024 characters.
What the rule is
The specification caps `description` at 1024 characters. This is the format's own ceiling — it's distinct from, and looser than, the tighter per-runtime budgets covered by SKM-P07 (OpenClaw's ~160-character guidance, Claude Code's practically-reported ~200).
A description this long is usually trying to do the job of the markdown body — enumerating steps or options — rather than stating a trigger condition.
Where it comes from
- Agent Skills — SpecificationSpecification
Which runtimes enforce it
| Runtime | Effect | Note |
|---|---|---|
| Claude Code | Not documented | The spec states the limit; no runtime documents what happens to a description that exceeds it (as distinct from the tighter runtime budgets below the spec ceiling — see SKM-P07). |
| Codex | Not documented | The spec states the limit; no runtime documents what happens to a description that exceeds it (as distinct from the tighter runtime budgets below the spec ceiling — see SKM-P07). |
| Cursor | Not documented | The spec states the limit; no runtime documents what happens to a description that exceeds it (as distinct from the tighter runtime budgets below the spec ceiling — see SKM-P07). |
| OpenClaw | Not documented | The spec states the limit; no runtime documents what happens to a description that exceeds it (as distinct from the tighter runtime budgets below the spec ceiling — see SKM-P07). |
| Hermes Agent | Not documented | The spec states the limit; no runtime documents what happens to a description that exceeds it (as distinct from the tighter runtime budgets below the spec ceiling — see SKM-P07). |
How to fix it
- Trim `description` to under 1024 characters. If it's carrying procedural detail, move that into the markdown body instead — the description only needs to state when the skill applies.
Elsewhere
- SKILL.md, the formatThe full frontmatter field table this rule is drawn from.
- Agent Skills Not WorkingThe diagnostic reference this rule’s portability and failure evidence comes from.
- All rulesEvery check the validator runs, grouped by class.