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

No annotations are provided, so the description carries the burden of behavioral disclosure. It adds useful context that the payment includes optional taxes and insurance (PITI). However, it omits details about return format, rounding, or the source URL/locale behavior hinted by the locale parameter, and includes irrelevant hosting info ('Runs on smart-tools.xyz').

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 sentence and reasonably short, but a significant portion ('Runs on smart-tools.xyz') is irrelevant and wastes tokens. It could be tightened to the core content without losing meaning.

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?

With 7 parameters and no output schema, the description fails to explain what the result looks like (e.g., a single number, a breakdown, or a URL). It also ignores the locale parameter entirely, which is unexpected. The description is too sparse to fully prepare an agent to use the tool 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?

Schema description coverage is 100%, so the baseline is 3. The description adds only a minor grouping of optional parameters (down payment, tax, insurance) under PITI, but does not clarify the purpose of the locale parameter or the source_url link. It provides little beyond what the schema already states.

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 computes a 'monthly mortgage payment' and explicitly mentions inclusion of optional down payment, property tax, and insurance (PITI). This is specific to mortgages and helps differentiate from general loan calculators, though it does not explicitly name an alternative sibling tool.

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 provides no guidance on when to use this tool versus sibling tools like loan_calculator or other financial calculators. It states what it does but gives no context on selection criteria or exclusions.

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