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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds the active-listings filter and mentions that output includes buy/rent stock and asking-price ranges, but it does not disclose potential edge cases such as unsupported communes or result-volume behavior.

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 one clear sentence that front-loads the action and resource, then adds the key qualifiers ('active listings', 'supported Luxembourg town', 'buy/rent stock and asking-price ranges'). Every part earns its place with no filler.

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 tool is simple, has full schema coverage, annotations, and an output schema, so the description does not need to explain return values or safety. It covers the resource, scope, and output focus; it only lacks explicit sibling routing or error-behavior guidance, which would make it fully complete.

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 100%, so the schema already documents both parameters, including the locale enum and commune name/slug format. The description's mention of a 'supported Luxembourg town' adds little beyond the schema, so the 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 uses a specific verb ('Get') and names the precise resource: estate agencies with active listings in a supported Luxembourg town. It distinguishes itself from sibling tools by focusing on agencies rather than individual listings, market estimates, or inquiries.

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 intended use case is implied clearly: call this when you need agency-level stock and price-range information for a town. However, it does not explicitly state when not to use it, nor does it mention alternatives such as search_for_sale or search_rentals.

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