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

No annotations are supplied, so the description carries the full burden and does disclose meaningful behavior: the tool is ungated and works for all users including Free/vault-only, and results are grouped by pack with per-skill usage hints. It still does not explicitly state that it is a non-mutating read or whether any rate/auth limits apply, keeping it below 5.

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?

Front-loaded with the core action in the first sentence, followed by the return shape and availability note. The trigger-phrase list is longer than strictly necessary but earns its place for routing, so the description is efficient overall.

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 zero-parameter, read-style listing tool with an output schema already defined, the description supplies what the schema cannot: what the listing contains, how it is organized, and that it is available to all tiers. Nothing needed to invoke it correctly is missing.

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?

The tool takes zero parameters, so the baseline of 4 applies; there is no parameter semantics for the description to clarify or omit.

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?

States a specific verb and resource ('Show all TigerTiger skills') plus scope ('available on the user's plan, grouped by pack'), so the agent knows exactly what comes back. It does not explicitly differentiate itself from the sibling 'capabilities', which is the one plausible overlap, so it stops short of a 5.

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?

Provides concrete trigger phrases ('list skills', 'what skills do I have', etc.) and an availability condition ('ungated — works for all users including Free (vault-only)'). It gives clear when-to-use context but never names an alternative tool or a when-not-to-use case.

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