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

Annotations already declare readOnlyHint, idempotentHint, non-destructive, and closed-world behavior, so the description does not need to repeat safety details. It adds useful behavioral context by specifying that the tool returns surplus/shortfall, required NOI, and the highest workable rate, though it does not state modeling assumptions such as amortization treatment.

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 definition is one front-loaded sentence that states the scenario and the returned results without filler. It is appropriately sized for a focused calculation tool.

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 read-only calculation tool with full schema coverage and annotations, the description is nearly complete: it explains the scenario being tested and summarizes the output. It could be stronger if it noted key modeling assumptions or how optional constraints like max_ltv and min_dscr shape the 'highest workable rate' result.

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 parameter meanings are already well documented in the input schema. The description does not add syntax, defaults, or interpretation guidance beyond what the schema provides, making the baseline 3 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 states a specific test — whether a bridge loan can refinance into permanent debt at stabilization — and previews the outputs. It is clear enough to distinguish from siblings like refinance_break_even or size_loan in practice, but it does not explicitly contrast itself with those alternatives.

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 use case is implied by 'bridge loan refinances into permanent debt at stabilization,' so an agent can infer when this applies. However, there is no explicit when-not guidance, no named alternative for nearby scenarios, and no mention of prerequisites such as stabilized NOI being available.

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