Explain an installed skill

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is well covered. The description adds valuable context beyond annotations by clarifying the tool does not execute the skill or dump its full prompt, and that it requires an exact match. This effectively communicates key behaviors without contradicting the annotations. It doesn't address error behavior for non-existent skill names or exact-match failure cases, which would push it to a 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?

The description is a single concise sentence front-loaded with the primary purpose, followed by two clarifying exclusions. Every word earns its place, with zero filler. This is an exemplar of efficient, well-structured tool documentation.

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 read-only metadata lookup tool with a single parameter, strong annotations, and no output schema, the description is largely complete. It covers the core function and what it deliberately avoids (execution, full prompt dump). Minor gap: it doesn't describe what a failed lookup (nonexistent name) returns, which could matter for an agent handling errors. With simple tool complexity, this is near-complete but not exhaustive.

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 100% (the single 'name' parameter is documented as 'Exact skill name' in the schema itself). The description adds marginal value by reinforcing the 'exact' constraint on the name, but since the schema already documents the parameter fully and there's only one trivial string parameter, the baseline 3 is appropriate.

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 uses specific verb+resource ('Return metadata and duplicate locations for an exact installed skill name') and clearly distinguishes behavior from related operations by stating 'without executing it or dumping its full prompt.' This effectively differentiates from sibling tools like search_skills which imply broader search. However, 'metadata' is somewhat vague about what specific attributes are returned, and the exact distinction from siblings like inventory_skills could be sharper.

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 implies usage context by specifying 'exact installed skill name' and clarifying it does NOT execute or dump full prompts, which guides an agent toward when this tool is appropriate versus inventory (listing all) or search/recommend (finding). However, it doesn't explicitly name alternative sibling tools or give explicit 'when/when-not to use' guidance, so it stops short of a 5.

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