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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so safety is covered. The description adds real value beyond that: it discloses the return payload shape (including a fraud warning when a post asks for money before a viewing) and that a bkkradar.com link is returned, which the agent could not infer from the schema.

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 front-loaded sentence with no filler; the provenance ('found by search_condos or nearby_condos') comes first and the payload detail follows. The field enumeration is long but each item tells the agent what data is available, so it mostly 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?

With no output schema, the description does the work of describing the return payload, and annotations cover the safety profile, so an agent can call this confidently. Minor gaps remain: no note on what happens when the id is unknown or expired, and no unit/currency note for price.

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%, with both the uuid id and the lang enum fully documented inline, so the description carries no burden here. It only hints that a link is returned, without noting that lang affects titles and links, so it adds no meaning beyond the schema. 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?

States a specific verb and resource ('Details of one listing') and immediately ties it to the sibling tools that produce the id (search_condos, nearby_condos). The enumerated field list (price, size, bedrooms, furnishing, pets, deposit, minimum lease, amenities, station/walk, scam warning, link) makes it unmistakable versus the search siblings.

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 phrase 'found by search_condos or nearby_condos' routes the agent clearly: call this after a search to expand a single result. It does not state explicit exclusions (e.g. 'do not use to browse many listings') or error behavior for a stale id, 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.