market_listings

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

There are no annotations, so the description carries full responsibility for behavioral disclosure. It only states the content (skills with prices) but does not mention whether the results are sorted, filtered, paginated, or if any side effects occur. While it implies a read-only listing, this is not explicitly stated. For a simple listing tool with no parameters, the lack of behavioral detail is a noticeable gap.

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, front-loaded sentence that directly states the tool's purpose. It is concise with no filler or redundancy. Every word contributes to the meaning, making it appropriately sized for a simple listing tool.

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 zero-parameter listing tool with no output schema and no annotations, the description covers the essential information: what is returned (skills) and the unit (credits). It does not specify ordering or filtering, but given the simplicity and the presence of sibling tools, this is adequate. An agent can call this tool correctly with the current description.

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 tool has zero parameters, so the baseline is 4. The description adds no parameter-specific detail, but none is needed since the schema is empty and coverage is perfect. The tool's behavior is fully defined by its lack of inputs, so no additional parameter semantics are required.

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 lists skills available for sale in the market with their prices in credits. It uses a specific resource (skills) and context (market), making the purpose unambiguous. It does not explicitly differentiate from sibling tools like marketplace_info, but the specificity of 'skills currently for sale' is sufficient for most agents to infer its distinct role.

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?

No guidance is provided about when to use this tool versus alternatives. Sibling tools such as marketplace_info or purchase_skill could serve related but distinct purposes, yet the description does not mention any conditions or preferability. An agent must guess based on tool names alone.

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