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 states that every launched listing is ownership-verified and lists the verification methods, adding context beyond a plain 'fetch.' However, it does not disclose error behavior for invalid slugs, potential pagination limits, or any side effects. It is a read operation, but the description does not mention read-only status or rate limits, leaving some uncertainty.

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 compact and front-loaded with the core purpose. It uses three sentences: the first lists the full scope of return fields, the second provides important ownership-verification context, and the third clarifies the inclusion of alternatives. Every sentence adds meaningful information with no fluff or repetition.

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?

Given that there is no output schema, the description reasonably covers the important return fields and gives background on ownership verification. It also mentions the canonical URL and inclusion of alternatives, which are likely useful for the agent. It could be more complete by specifying behavior for not-found slugs or whether the alternatives list is exhaustive, but for a simple getter it is sufficiently complete.

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% description coverage for the only parameter 'slug', including an example and source context ('from search results or the listing URL'). The tool description adds only 'Fetch by slug' which is redundant. There is no additional semantic value beyond what the schema already provides, so the 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 uses the specific verb 'Fetch' and clearly identifies the resource as 'the full toolfound listing for a product by slug.' It enumerates the exact fields returned (description, tagline, pricing model, tags, socials, vote count, launch date, ownership-verification status, canonical URL), which differentiates it from siblings like get_badge (badge-only) or get_alternatives (alternatives-only). The scope is precise and 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 description does not explicitly state when to use this tool versus alternatives. It mentions that the tool includes top alternatives, which could be confused with the dedicated get_alternatives sibling, but provides no guidance on which tool to choose for specific needs. There are no exclusions or conditions. The usage context is only implied through the resource description.

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