calculate_us_child_tax_credit

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

No annotations are provided, so the description carries full burden. It indicates the return format ({agi, base_credit, credit_reduction, final_credit}), suggesting a read-only calculation. However, it does not explicitly state that it is a safe, non-destructive operation or disclose any authentication/rate limit requirements, leaving room for ambiguity.

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 extremely concise with two sentences: one states the main purpose and return format, the second directs to related tools. No superfluous words; every sentence adds value.

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 simple calculator with 3 parameters and no output schema, the description covers purpose, return fields, and hints at related tools. It lacks explicit mention of required parameters (though schema covers it) and detailed phase-out mechanics, but is largely adequate for an agent to understand and invoke correctly.

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?

Input schema covers all parameters with descriptions (100% coverage). The description adds no additional semantic information beyond 'phase-out based on AGI', which is already implied by the AGI parameter. Baseline 3 is appropriate.

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 specifically states 'Calculate US Child Tax Credit for 2026 with phase-out based on AGI', providing a clear verb+resource combination. The specificity of 'US Child Tax Credit' and '2026' distinguishes it from many other US tax calculators among sibling tools.

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 indicates the tool calculates the US Child Tax Credit and points to list_bundles for related calculators. However, it does not explicitly state when to use this tool over alternatives (e.g., calculate_us_federal_tax) or when not to use it, though the purpose is narrowly defined.

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