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 discloses the critical limitation that no paid data is delivered, which is a key behavioral trait. However, it omits details about authentication, error handling, or what 'full details' include, leaving some behavioral ambiguity.

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 sentences, tightly written, and front-loaded with the primary purpose. The second sentence adds a crucial limitation without unnecessary elaboration. 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 simple tool with one parameter and no output schema, the description covers the core purpose and key limitation. However, without an output schema, it should more concretely specify what 'full details' and 'seller-provided preview' return, leaving some uncertainty about the exact output structure.

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 schema has one required parameter (listing_id) with 0% description coverage. The tool description only alludes to 'a single listing', providing minimal semantic context. It does not specify the format, source, or constraints of the listing_id, failing to compensate for the lack of schema-level detail.

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 a specific verb ('Get') and resource ('full details and seller-provided preview for a single listing'). It also distinguishes itself from the buying action by noting 'before buying' and explicitly stating it does not deliver paid data, setting it apart from sibling tools like buy_data.

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 for when to use the tool ('before buying') and an explicit exclusion ('Does not deliver the paid data'). However, it does not name alternative tools directly, so the guidance is clear but not fully explicit about when to use a different sibling tool.

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