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

With no annotations, the description carries the full burden and does so thoroughly. It discloses the paid nature ($0.10), the output format (line-by-line amounts with instrument citations), the existence of an explicit refused list for unpriced schemes ('unknown, not zero'), and the authentication/payment flow (api_key vs x402). This is a transparent, behavior-rich description.

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 compact paragraph that front-loads the cost and core function, then adds exclusions, output details, and payment behavior. Every sentence earns its place; there is zero fluff or redundancy, and the structure logically flows from purpose to alternatives to caveats.

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 11 parameters, the schema fully covers them, so the description need not repeat them. The description explains the return format (line-by-line with citations and refused list), the payment/auth mechanism, and the boundary with income tax. Given the schema coverage and the described behavior, nothing essential for an agent to invoke the tool correctly is 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?

Schema description coverage is 100%, so the schema already documents every parameter. The description mentions gross salary and api_key but does not add meaning beyond what the schema provides. Per the rubric, a baseline of 3 is appropriate when the schema does the heavy lifting; the description adds no supplementary parameter semantics.

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 clear verb+resource ('Cost to employ') and specifies exactly what it computes: 'every statutory contribution on both the employee and employer sides for a gross salary'. It also differentiates itself from sibling tools by explicitly stating it does NOT compute income tax and directing to compute_payroll, making its purpose unambiguous and distinct.

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 gives explicit when-not-to-use guidance ('Does NOT compute income tax — use compute_payroll for gross-to-net take-home where supported') and names the alternative tool. It also instructs on api_key usage and what happens without it ('otherwise the response explains how to pay via x402'), covering both context and exceptions.

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