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 that results come from Pionra and can be filtered by budget/rooms, but it does not disclose other behavioral traits such as result ordering, URL/locale behavior (though lang schema covers this), or pagination. 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?

The description is a single, efficient sentence with no filler. It front-loads the verb and resource, then immediately states the key filters. Every word earns its place.

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 read-only listing tool with five optional parameters and no output schema, the description covers the core intent and main filters. It does not clarify whether a city is expected for meaningful results, nor does it explain what the returned listings look like. Given the annotations already handle safety, this is adequate but not rich.

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 only 20% (only 'lang' is described), so the description must compensate. It usefully maps 'city' to city, 'budget' to max_price, and 'room count' to min_rooms. However, it omits 'limit' and 'lang'; lang is already described in the schema, but limit is left undocumented in both. The mapping is helpful but incomplete.

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 names a specific verb ('Find'), a concrete resource ('housing listings on Pionra'), and the key filtering dimensions (city, budget, room count). This clearly distinguishes it from sibling tools like find_jobs and search_pionra; an agent can infer what this tool does without opening the schema.

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 usage context is implied: use this tool when the user wants housing listings on Pionra, filtered by city/budget/rooms. However, there is no explicit guidance on when to prefer find_housing over search_pionra or find_jobs, and no exclusions are stated, leaving some selection ambiguity.

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