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

Annotations already establish read-only and open-world behavior; the description adds 'recomputed nightly' and the fact that sample sizes back each figure, which tells the agent to expect shifting computed values. No contradiction with annotations.

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?

Two tight sentences with the main result front-loaded and the freshness warning in a short second sentence. Every clause adds distinct information.

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?

It describes the return content and refresh cadence well for a simple read-only stats tool, but the undocumented city parameter and the lack of any guidance about alternatives leave a real gap. No output schema means the description carries more of the burden.

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 schema has one undocumented `city` parameter with 0% schema coverage, and the description never mentions it. The title suggests Da Nang, but an agent cannot tell whether `city` filters results or whether omitting it defaults to a fixed market.

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 identifies the resource ('median rents by size and district') and enumerates its content, so it is easy to tell apart from listing/building tools. It lacks an explicit verb like 'returns', which keeps it from a 5.

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 content implies this is for aggregate rent statistics rather than individual listings, and 'recomputed nightly' signals freshness, but it never states when to prefer it over search_listings or get_listing.

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