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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), so the description's job is to add context — and it does: it flags the tool as EXPERIMENTAL (beta), declares it 'Free', and states the minimum search length. It does not say whether the beta catalog is stable or how large result sets are paginated/limited.

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?

A single dense sentence plus a fragment, with the beta warning and the value proposition front-loaded. It reads as telegraphic rather than prose, but nothing is redundant and no sentence wastes space.

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 two parameters and no output schema, the description should carry the return shape — 'with the sample behind each' conveys that a count accompanies each location, but the actual response fields (location name, teryt identifier, metric, n) are never described. The beta caveat and cost signal are present, leaving the tool mostly, but not fully, specified.

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 coverage is 100%, so both parameters are already documented, including the enum semantics and the minLength=2 constraint that the description merely repeats. The description's one genuine addition is the hint that flood_risk coverage is county-level while the others are city-level, which the schema buries in the enum text. Baseline 3 applies.

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 states a specific verb+resource: listing cities/counties a given metric covers, along with the sample size behind each. It also ties the output to concrete consumers ('valid location/teryt values for get_rental_yield, get_price_spread or get_flood_risk'), which helps distinguish it from lookup siblings. It stops short of contrasting with list_locations, the most likely alternative for location enumeration.

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?

Usage is implied rather than stated: by saying the results are the valid location/teryt values for the three get_* tools, it hints this is a validation/coverage pre-check before calling them, and 'Omit for the full catalog' clarifies search behavior. There is no explicit when-to-use/when-not, and no guidance on choosing this over list_locations.

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