Cian Offer Card

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so safety is covered. The description adds real behavioral context beyond them: price_rub is None rather than 0 when no price is stated, and price_unit disambiguates 'total'/'month'/'day', which prevents a common misinterpretation.

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?

Three short paragraphs, front-loaded with what the card returns, followed by the two highest-risk semantic caveats and a doc pointer. Nothing is redundant with the schema or annotations.

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?

Output schema exists, so return-value detail is unnecessary, and the description still flags the price/unit traps and points to guide://cian/cian_card for the full field list and error codes. Only the sibling routing advice is missing.

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% and the single parameter already documents the accepted id-or-URL form, so the description adds no new input syntax. The value it adds (price nullability and unit meaning) concerns output interpretation rather than parameters.

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?

"Read one Cian offer" states a specific verb and single-resource scope, then enumerates the returned content (price/history, layout, building, address, metro, description, publisher). This clearly separates it from the sibling cian_search, which returns lists rather than one card.

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 singular-object framing implies you call it once you have an offer id or URL, and the parameter description reinforces that. However, it never explicitly says when to prefer cian_search or compare_prices instead, nor what to do when the id is unknown.

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