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

Annotations already establish read-only, idempotent, non-destructive, non-open-world behavior, so the bar is lower. The description adds substantial context beyond annotations: the HUD coverage tests, bank regulatory ceiling, HVCRE equity requirement, optional debt-fund branch, and return fields. It does not cover edge cases or error behavior, but it is well above what annotations alone provide.

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 front-loaded with the core action and is appropriately sized for a complex three-method sizer. It is a single dense sentence with parentheticals, which is concise but slightly harder to scan than structured sentences.

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?

Given 10 parameters, no output schema, and read-only annotations, the description supplies the key calculation methods and return fields (loan, binding limit, equity needed, interest). It is complete enough for invocation, though it lacks sibling differentiation and limitations that would fully resolve when to choose this tool over compare_construction_options.

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 all 10 parameters, including defaults and enum meaning. The description adds some conditional context for bank and fund loan-to-cost inputs but largely repeats what the schema already states. Baseline 3 is appropriate when schema does the heavy lifting.

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 names a specific verb and resource: it runs a construction loan sizer on a project and enumerates the three sizing approaches. An agent can tell what the tool produces, but the description does not explicitly distinguish it from sibling tools such as compare_construction_options.

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 implies when the tool applies (sizing a multifamily construction loan three ways) and explains conditional branches for bank and debt-fund loan-to-cost inputs. However, it gives no explicit when-not guidance and does not name alternatives or explain when to use compare_construction_options instead.

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