skill

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide no safety hints (all false), so the description carries the burden. It discloses that writes go to the `skill_substrate` namespace, that entries are schema-validated at write time, and that `on_conflict` can reject or replace. This gives useful behavioral context beyond the annotations, though it doesn't cover every edge case like permissions or rate limits, which is acceptable for this tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is long but well-structured with a summary, action list, example, and Args section. It is not wastefully verbose; every section covers a necessary aspect of a complex multi-action tool. It loses one point because it could be slightly tightened, but overall it remains readable and front-loaded.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a multi-action tool with 14 parameters and zero schema descriptions, the description is comprehensive. It covers all actions, parameter semantics, validation rules, an example, and the sibling differentiation. Since an output schema exists, the lack of return-value details is acceptable. The agent has enough context to select and invoke this tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, but the description compensates fully. It lists every parameter with context: action values, skill_id format (dot-separated lowercase), body length constraints, applies_to rules (1–10 lowercase_underscore, no hyphens), skill_type enum, on_conflict options, and which params apply to which action. This adds meaning far beyond the bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a clear verb-resource statement: "Substrate-native agent skill catalog — define, surface, record outcomes." It also distinguishes itself from sibling 'procedure' by explicitly saying skills are structured catalog entries, not loose how-to memories. This leaves no doubt about what the tool does and how it differs from nearby tools.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description states when to use each action and provides an explicit alternative: "different from loose how-to memories (use `procedure` for those)." It also gives a concrete workflow example (define → surface → outcome) that teaches the agent when to invoke which action, making usage guidance highly actionable.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.