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

Annotations (readOnlyHint=true, openWorldHint=false) cover safety and closed-world behavior. The description adds that the score is a composite of 8 layers and notes 'Updates: on source cadence,' but it fails to explain how the target county is specified given the schema has no county parameter. This omission leaves the agent uncertain about invocation context, which is a behavioral transparency gap beyond what annotations cover.

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 tightly written in two sentences plus a short updates note. The first sentence packs the core purpose, scope, and output composition; the second provides explicit usage scenarios. Every sentence contributes, with no fluff or repetition.

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 output components and when to use the tool, but critically omits how the tool knows which county to evaluate—there is no county parameter in the schema. An agent reading 'for any US county' might expect a county_fips argument that doesn't exist. This is a significant completeness gap for a tool that otherwise has minimal parameters and no output schema.

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 parameter `days` is fully documented in the schema with description (history series, Gold tier requirement, default snapshot). The main description adds no parameter-specific information and never mentions the optional history feature. With 100% schema description coverage, baseline 3 is appropriate; the description does not increase understanding of the parameter.

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 'Returns a 0-100 local real-estate market strength score for any US county' and lists the output components (composite_score, component_scores, named drivers, coverage). It also provides concrete use cases (good buy, rental, development target, timing decisions), and the mention of '8 AlpineDataWorks place-intelligence layers' and 'joined on county_fips' distinguishes it from sibling 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?

The description gives explicit guidance on when to call: 'when the user asks whether a property, housing market, county, or metro is a good buy, rental, or development target, or when timing a purchase, lot acquisition, or market-entry decision.' However, it does not name alternative tools or state when not to use this tool, though the use cases are specific enough to imply exclusivity.

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