get_merchant_stats

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 implies a read-only operation through the verb 'Retrieve', which is a positive indicator. However, it does not disclose potential rate limits, authentication requirements, or whether the data is real-time or aggregated with a delay. Given the zero annotation coverage, a 3 is appropriate: the description conveys the core behavior but omits deeper operational context.

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, tightly worded sentence that lists the key outputs without any redundancy or filler. Every word contributes meaning: 'Retrieve' indicates the action, the rest specifies the exact data. It is front-loaded with the verb and resource, making it easy to scan.

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 tool with no output schema, the description provides a solid enumeration of return categories, which is sufficient for an agent to understand what it will get. It lacks information about response format or typical use cases, but since there are no parameters to configure and the output is straightforward, the description is nearly complete. A score of 4 reflects the minor gap of not stating when to prefer this over sibling metrics tools.

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 there are no parameter semantics to clarify. According to the guidelines, 0 params corresponds to a baseline of 4. The description adds value by summarizing what data will be returned, which indirectly informs the agent of the tool's scope. No parameter information is needed.

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 retrieves merchant analytics and enumerates specific data categories: volume analytics, invoice counts (paid/pending/expired), net revenue, and compliance tier limits. It uses a specific verb (Retrieve) with a clear resource (merchant stats), making the purpose unambiguous and distinguishable from sibling tools like get_profile or list_invoices.

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 implicitly indicates this is for fetching aggregated merchant statistics, but it does not explicitly state when to use this tool versus alternatives. For example, it does not mention that this is for overview-level metrics compared to get_invoice_details for individual invoice data. No alternatives or exclusions are given, but the purpose is clear enough that an agent could infer appropriate usage.

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