Worth Sheet: apartment building value at today's loan rates

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint=false, and destructiveHint=false. The description adds meaningful context beyond that: it discloses the as-of dates, the conditional availability of prior readings, the publisher link, and the specific loan-limit definitions from the term sheets.

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 main data types and is dense but efficient. The single long sentence with a semicolon is slightly run-on, but every clause contributes useful detail about what is returned.

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?

There is no output schema, so the description carries the burden of explaining return contents. It does this thoroughly for a no-parameter read-only retrieval tool by listing the rates, dates, prior readings, publisher link, loan limits, and spread note, though 'spread note' remains somewhat undefined.

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?

This tool takes zero parameters, so there are no parameter semantics to explain. The baseline for a no-parameter tool is 4, and the description does not need to compensate for missing schema parameter descriptions.

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 the specific resources retrieved: 5-, 7-, and 10-year Treasury par yields, overnight SOFR, as-of dates, prior readings, publisher link, loan limits, and spread note. It is clear what the tool returns, but it does not explicitly differentiate itself from siblings like rate_sensitivity or value_at_rate.

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 retrieval of current rate and loan-limit data, but it gives no explicit guidance on when to use this tool versus the sibling tools rate_sensitivity and value_at_rate. There are no stated exclusions or alternative conditions.

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

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

Annotations already declare this a read-only, idempotent, closed-world computation, so the safety profile is covered. The description adds real behavioral substance beyond that: the sizing is income-limited via DSCR as well as LTV, the ladder is centered on today's Treasury by default, and the default scenario set is -100 to +100 bp. It does not describe the shape of the returned ladder (units, length), which is the remaining gap given no output schema.

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?

Two sentences with no filler; the key defaults and the ladder range are front-loaded ahead of the example question. The first sentence is syntactically dense and slightly hard to parse on a first read, which costs a point.

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 ten-parameter pricing model with no output schema, the description conveys what is being solved (constrained price and loan size), the default scenario grid, and the default underwriting assumptions. What is missing is the return shape — whether the output is a table keyed by shift, and in what units — which matters for an agent that must interpret results.

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% and all ten parameters carry defaults and rationale (agency term sheets, placeholder spread, tax reset semantics), so the schema does the heavy lifting. The description only corroborates the 80% LTV, 1.25x DSCR and default shift range rather than adding new meaning. 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 states a specific computation on a specific resource: it solves the price a financed buyer can carry and the income-limited loan size across a ladder of 10-year Treasury shifts for a given NOI. That is far more than a restatement of the name. It does not explicitly name the sibling it is not (value_at_rate, get_rates_and_loan_limits), so an agent must infer the difference from the 'ladder' framing.

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?

Usage is conveyed only by the illustrative question ('what is my building worth to a buyer if rates drop half a point?') and the ladder framing. There is no explicit when-to-use or when-not-to-use statement, and the sibling value_at_rate is never mentioned even though the two are close enough to confuse an agent.

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

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds that the result is an estimate from supplied numbers, not an appraisal, and notes the latest Treasury default, which is useful behavioral context without contradicting annotations.

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 purpose and outputs are front-loaded in a compact two-sentence description despite the tool's complexity. Every clause carries relevant information, and the appraisal caveat is appropriately placed at the end.

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 no output schema, the description does the important work of naming the returned metrics: NOI, expense ratio, value range, financed-buyer price, per-unit value, and refinance loan. It is complete enough for invocation, though output formatting is not specified.

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 itself documents all 23 parameters thoroughly. The description reinforces the main inputs and defaults but does not add much parameter-level detail beyond what the schema already provides.

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?

States a specific verb and resource: runs a named valuation worksheet for 5+ unit apartment buildings and lists the main outputs. It is clear what the tool does, but it does not explicitly differentiate itself from the sibling rate 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?

Makes the usage context clear: rent roll plus a year of expenses, or a known NOI. It does not explicitly say when to choose this over get_rates_and_loan_limits or rate_sensitivity, but the input conditions are clear.

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