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

Annotations already mark the tool read-only and non-destructive, and the description adds meaningful behavioral detail: the waterfall ordering, inclusion of NY CEMA savings, and a critical consequence of omitting prepaymentPenaltyPercent. This goes beyond the annotation-only safety profile, though edge-case handling and output specifics are not covered.

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?

Three dense sentences, front-loaded with the primary behavior, followed by an important caveat. No filler or repeated schema content; every sentence earns its place.

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 an 11-parameter financial tool with no output schema, this description gives a good high-level picture and the most critical input caveat, but it leaves gaps: exact dollar/percent units are largely implicit, the closing-cost source is not reflected in the schema, and the output return format is not specified. It is adequate for selection but not fully complete for invocation without relying on parameter names.

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?

With only 18% schema description coverage, the description partially compensates by explaining the prepaymentPenaltyPercent requirement and linking maxLtv, minDscr, and minDebtYield to the LTV/DSCR/debt-yield constraints, plus the NY CEMA condition. Several parameters like noi, propertyValue, and amortizationYears rely on self-evident names and are not explicitly defined.

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 operation ('cash-out refinance waterfall') and states the exact output: the largest new loan supported across LTV, DSCR, and debt-yield, then net cash after payoff, prepayment penalty, and closing costs. This clearly distinguishes it from siblings like size_loan or estimate_closing_costs.

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 phrase 'Full cash-out refinance waterfall' establishes a clear invocation context, and the NY CEMA remark adds a conditional use case. It does not explicitly name sibling alternatives or exclusion conditions, so it falls short of a full routing guide.

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