check_listing

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

Annotations already carry readOnlyHint, idempotentHint, and destructiveHint, and the description adds significant behavioral context: 'Deterministic, no model', the vocabulary limitation, and the precise meaning of PUBLISH ('nothing unbacked was found, not verified true'). This goes far beyond the annotations and helps the agent set correct expectations. No contradiction with annotations exists.

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 first sentence front-loads the core purpose, and every subsequent section earns its place: behavior, return shape, decision logic, and parameter details. The argument breakdown is cleanly separated from the behavioral notes, and there is no redundant or filler content.

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?

Despite having no output schema, the description specifies the exact return structure with fields, the decision values (PUBLISH/REVIEW), and how to interpret the results. It also explains the determinism limitation and gives enough parameter guidance to call the tool correctly. For a read-only checker with no siblings, this is 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?

Schema description coverage is 0%, so the description must carry the full semantic weight. It provides a concrete example of the 'specifics' object with realistic keys and values, explicitly notes that 'includes' is a lowercase item list, and defines 'title' and 'description' as the AI-written listing text. This fully compensates for the empty schema descriptions.

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 specific verb+resource: 'Check an AI-written marketplace listing against the seller's item specifics before it's published.' It enumerates the exact claim categories checked and the statuses assigned, so the tool's purpose is unambiguous. No sibling tools exist, so differentiation is not needed, but the description still makes the scope clear.

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 clearly states the intended use case ('before it's published'), defines the decision rule ('Any claim that isn't SUPPORTED means REVIEW'), and warns against over-interpreting PUBLISH. It does not explicitly discuss when not to use the tool, but because there are no sibling tools, this is a minor gap rather than a critical one.

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