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

With no annotations provided, the description carries the full burden of behavioral disclosure. It details exactly what each entry contains (SKILL.md URI, name, description, frontmatter, sha256 manifest), which is behavioral transparency about the return payload. It does not explicitly state read-only behavior, but the act of listing and the mention of a separate read tool strongly imply it. This is adequate for a list operation.

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 two concise sentences with no filler. The primary purpose is stated first, followed by a precise enumeration of the return contents and a clear pointer to the sibling tool. Every word earns its place.

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 parameterless list tool with no output schema, the description fully specifies what an agent needs: the action, the content of each entry, and how to proceed to read a skill body. No critical information is missing for correct invocation and interpretation.

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 has zero parameters, so the input schema is trivially complete (100% coverage). The description adds value by describing what the returned list entries contain, which goes beyond the schema. Since there are no parameters to explain, the baseline of 4 applies, and the description enriches the usage context.

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 begins with a specific verb and resource: 'List this product's skills.' It clearly distinguishes itself from the sibling tools by naming `read_skill` as the companion for reading a body, and the pw_* tools are clearly unrelated to listing skills. The mention of what each entry contains further clarifies the tool's exact function.

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 provides clear context by stating it lists skills and explicitly directs the agent to `read_skill` for reading a body, which implies when to use this tool vs. its sibling. It does not list exclusions or alternative tools for other purposes, but for a listing operation, the guidance is sufficient.

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