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 reveals that the tool uses 'Latest CDN data' (implying up-to-date tax rates) and lists the tax components it considers, which adds some transparency. However, it does not state whether the operation is read-only, what the output structure looks like, what assumptions are made (e.g., income thresholds, deduction applicability), or any limitations. This is a moderate gap for a calculation tool.

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, efficient sentence that front-loads the primary action and then lists the key factors. It wastes no words and is immediately scannable. The use of a colon and comma-separated list is clear and structured.

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 calculation tool with 4 parameters and no output schema, the description covers the core purpose and main factors but omits important operational details: it does not describe the return value (e.g., a breakdown or a single number), does not mention any assumptions about tax years or income brackets, and does not clarify that it is US-specific (though state tax implies it). Given the complexity of tax calculations, an agent might need more guidance on what to expect from the output, so a 3 is warranted.

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 input schema has 100% coverage, so all parameters (w2Salary, contractorRate, state, filingStatus) already have descriptions. The tool description adds context by mentioning tax components like state tax and standard deduction, which implicitly connects parameters to their role in the calculation. This is a marginal improvement over the schema, but not enough to raise above the baseline 3 for a well-covered schema.

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 uses a specific verb ('Compare') and names the exact resources ('W-2 salary vs 1099 contractor rate'), making the purpose unmistakable. It also lists the key factors considered (SE tax, FICA, standard deduction, state tax), which distinguishes it from sibling tools like calculate_se_tax or calculate_freelancer_tax that focus on single calculations.

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 implies when to use this tool: when an agent needs to compare take-home pay between W-2 and 1099 employment. It does not explicitly mention alternatives or exclusions, but the comparison focus is self-evident and the sibling list shows other tax tools are for different purposes. A 4 is appropriate because it is clear enough without explicit when-not guidance.

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