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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds a little useful context by framing this as a freshness check ('whether it is still for rent'), implying availability can change, but says nothing about what happens for a delisted or unknown id, nor about auth or rate limits.

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, front-loaded with the resource and the returned attributes, followed by the input-provenance hint. Nothing is 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?

With an output schema, full parameter coverage, and read-only annotations, the description covers what an agent needs to select and call the tool. It is slightly short on edge-case behavior (invalid or delisted ids), but nothing essential is missing for a one-parameter lookup.

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% and the single parameter is fully documented as 'Apartment id or openigloo.com/unit/... link'. The description only restates this and adds the minor hint that the id typically comes from a search result, which is marginal value over the schema.

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?

States a specific verb+resource: 'Details of one apartment on Openigloo', then enumerates the fields exposed (availability, rent, move-in date, lease length, description, photos). The singular 'one apartment' implicitly separates it from search_apartments and nearby_apartments, though no sibling is named explicitly.

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?

'Pass an apartment id from a search result or an openigloo.com/unit link' gives clear workflow context: this is a follow-up call after a search or from an external link. No explicit exclusions or named alternatives are given, so it stops short of full when/when-not guidance.

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