Calculate maximum home price you can afford

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

Annotations include readOnlyHint=true, idempotentHint=true, openWorldHint=false. The description reinforces this by stating 'No network — pure local math,' and discloses the DTI rule. No contradictions.

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 concise (four sentences) and front-loaded with the purpose. Every sentence adds value without 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?

The description covers inputs and outputs adequately for a straightforward calculator. It mentions the output includes 'max home price, binding constraint, and PITI breakdown.' However, it does not specify default DTI values or behavior for optional parameters, which would enhance completeness.

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 inputs like 'monthly income, recurring monthly debts, down payment, interest rate, optional property-tax rate / insurance / HOA / loan term' but does not detail each parameter's meaning or defaults (e.g., front_end_dti, back_end_dti). The 28/36 rule implies defaults, but explicit mapping would improve clarity.

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's purpose: 'Solve for the maximum home price you can afford under the standard 28/36 DTI rule.' It lists inputs and outputs, and distinguishes from siblings like onehome_calculate_mortgage by specifying the DTI rule and local math.

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 explicitly states 'No network — pure local math,' clarifying it's a local calculation. It also notes 'Same math as zillow-mcp / redfin-mcp / compass-mcp / homes-mcp,' providing context for when to use. However, it does not explicitly exclude alternatives or provide when-not-to-use guidance.

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