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

With no annotations, the description must disclose behavioral traits. It implies a read operation via '取得する' and specifies returned fields, but does not explicitly state that the tool is read-only, idempotent, or error handling behavior (e.g., if shop not found). This is sufficient for a simple GET but could be improved.

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 that front-loads the action and lists key return data. No filler or redundant information, achieving high efficiency.

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 simple tool with one parameter and no output schema, the description covers the return data adequately. It could be enhanced by mentioning error cases or format details, but is mostly complete for operational use.

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 input schema has 100% coverage with parameter description 'ショップの slug（URL 識別子）'. The description adds 'slug で取得する' confirming the parameter role, but does not add substantial new meaning. Baseline score of 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 clearly states the tool retrieves details of one shop by slug and lists the returned data (story, description, supported blockchains, x402 payment status). It effectively distinguishes from siblings like list_shops (which returns multiple shops) and get_product (which returns product details).

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 when to use (when you need specific shop details by slug) but does not explicitly mention when not to use or suggest alternatives, such as using list_shops for browsing or get_product for product details. Guidance is adequate but could be more explicit.

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