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 useful context about the 2-5 market limit and side-by-side comparison, but it does not disclose other behavioral traits such as output format, data sources, or any limitations beyond the count. It provides some extra value beyond annotations but not rich detail, warranting a 3.

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 and front-loaded with the core purpose in the first sentence. The second sentence provides useful usage context. However, the final tagline 'USDV Capital — Your Real Estate CFO.' is promotional and does not add functional value for an AI agent, preventing a perfect score.

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 relatively simple tool with one well-documented parameter and clear annotations, the description covers the essential context: what it compares (investment metrics), how many markets (2-5), and the analytical level (CFO-level). It does not explain the return structure, but the lack of an output schema is mitigated by the tool's straightforward comparison nature. This is nearly complete for the tool's complexity.

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 input schema fully documents the 'locations' parameter with type, min/max items, and nested properties (name, state), giving 100% schema description coverage. The description reinforces the 2-5 market scope but does not add new parameter-level information. Since the schema already explains the parameters thoroughly, a baseline score of 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 clearly states the tool's function: 'Compare real estate investment metrics across 2-5 US markets side-by-side with CFO-level analysis.' The verb 'Compare' plus the explicit resource (real estate investment metrics) and scope (US markets) makes it distinct from sibling tools like markets-stats or calc-* tools. It directly communicates the tool's purpose without ambiguity.

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 provides a clear use case: 'Ideal for investors deciding where to deploy capital.' This tells the agent when to use this tool. However, it does not explicitly state when not to use it or name alternative tools for different scenarios, so it falls short of a 5.

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