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

With no annotations, the description must carry the behavioral load. It discloses the ownership scoping and enumerates the return fields (prompt, required tools, source, model), which is genuinely helpful. It says nothing about pagination, ordering, rate limits, or auth requirements, but for a zero-parameter read-only list the risk surface is small.

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?

Two short sentences, front-loaded with the action and scoped by 'you own', with the second sentence efficiently supplying the domain definition and the payload shape. No waste.

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 no-argument list tool with no output schema, the description compensates well by naming the fields returned (prompt, required tools, source, model). Only minor details like ordering or result volume are absent, which is acceptable at this complexity.

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 no parameters (schema coverage 100% trivially), so per the baseline a 4 is appropriate; there is no parameter semantics to add meaning to.

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 ('List the skills you own') and even defines what a skill is, so an agent unfamiliar with the domain understands the entity. It doesn't explicitly name or differentiate from the sibling create_skill/delete_skill tools, but the list verb plus the ownership scope makes the distinction unambiguous.

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 phrase 'you own' implies the context (retrieving only the caller's own skills), which is useful scoping guidance, but there is no explicit when-to-use statement, no exclusions, and no pointer to alternative tools for discovering skills you don't own.

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