Calculate maximum home price you can afford

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

Annotations already declare readOnlyHint and idempotentHint, covering safety. The description adds that it performs pure local math with no network, and describes outputs including the binding constraint and PITI breakdown, providing useful behavioral context beyond the 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?

The description is compact and well-structured: purpose first, then input/output summary, and a note on external equivalence. Every sentence earns its place with no redundancy.

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 10-parameter tool with no output schema, the description gives a high-level overview but omits details like the optional DTI overrides, units for tax rate, and potential error conditions. It mentions the main output components, which helps, but it is not fully complete for correct invocation.

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 0%, so the description must compensate. It lists key inputs like monthly income, debts, down payment, interest rate, and optional property tax, insurance, HOA, loan term. However, it does not explain units (e.g., property tax rate as decimal vs percent) nor mention optional overrides for front/back-end DTI ratios, leaving ambiguity.

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 solves for the maximum home price under the 28/36 DTI rule, with a specific verb and resource. It distinguishes from siblings like onehome_calculate_mortgage by focusing on affordability, though it does not explicitly contrast with that sibling.

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 does not provide guidance on when to use this tool versus alternatives like onehome_calculate_mortgage. It lists inputs and outputs but lacks explicit when-to-use or when-not-to-use conditions, nor any exclusions.

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