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

Annotations already establish readOnly/idempotent/non-destructive, so the bar is lower; the description still adds real behavior context by disclosing the 14-day cache window, which explains why a call may return instantly and may not reflect fresh data. It does not say whether the call incurs cost or what happens on a non-U.S. or unparseable address, so it stops short of a 5.

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?

One dense, front-loaded sentence that moves from action to output contents to caching behavior with no filler. The long enumeration of report sections is informative but sits close to what the output schema already conveys.

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 an output schema present the description needn't explain return values, yet it summarizes report contents for selection purposes and adds the caching caveat. The remaining gap is routing versus check_home_value_report and failure behavior for unsupported addresses.

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?

The single address parameter is fully documented in the schema (100% coverage) including formatting and a condo-unit note, so the schema carries the load. The description only implies the input is a U.S. residential address and adds no format or normalization details beyond that.

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 gives a specific verb+resource ("Pull a CPF Mortgage home value report") and enumerates the report's contents, so an agent knows exactly what it gets back. It does not explicitly distinguish itself from the sibling check_home_value_report, leaving the reader to infer the split between pulling and checking.

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?

"for a U.S. residential property" narrows applicability and the 14-day caching note implies this is the pull-and-generate path, but there is no explicit statement of when to use this versus check_home_value_report, nor any prerequisite or exclusion guidance.

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