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

There are no annotations, so the description carries full burden for behavior. It explains the zero-storage broker model, that only metadata and a scrubbed preview are stored, that the real deliverable is relayed from a verified endpoint, what consent means, and that price_cents 0 equals free. This is substantially more than the name alone could imply.

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 dense but each section has a purpose: operational scope, storage behavior, setup prerequisite, metadata-only constraint, pricing, consent, and health-data exclusion. It front-loads the core action and adds details in a logical order without 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?

For a tool with 8 parameters, no output schema, and no annotations, the description provides enough directly relevant context to call it correctly: preconditions, consent expectations, what payload may be sent, endpoint registration, and related route. Nothing required for a correct sell_data invocation appears to be missing.

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?

Although the schema already documents most fields, the description reinforces key parameter intent: preview must be small and already-scrubbed, consent confirms ownership, price_cents 0 means free, and the seller must have a verified delivery endpoint. The description does not add much beyond the schema for category and vertical, but it adds critical semantics for the most meaningful fields.

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 opens with a precise action: 'Publish a per-purchase listing for any asset type' and enumerates the accepted categories. It also distinguishes the tool from list_health_data, making clear that health data is not sold through this path.

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?

It gives a concrete prerequisite: 'Register + verify that endpoint first with set_delivery_endpoint.' It also states the when-not-to-use case, explicitly routing personal health data to list_health_data instead.

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