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

Annotations already declare readOnlyHint, non-destructive and closed-world, and the description adds real context: it is read-only and replies must be posted in the cabinet, so the agent knows replying is out of scope here. It also discloses the thread-message default of 5 and cap of 20, which the annotations do not. It does not discuss pagination or failure behavior for an unknown ticket number.

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?

Front-loads the core operation, then the returned field list, then the limiting/read-only caveat — a sensible order with no filler. The field enumeration is long but earns its place because there is no output schema; the Ukrainian example queries are the only borderline element.

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 enumerates the meaningful return fields (status, assignee, client, waiting-for-reply flag, thread messages) so the agent knows what it will get. Input format, the messages default/cap, and the read-only boundary are all covered for a simple 2-parameter tool.

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 50% — the 'ticket' param is documented but 'messages' has no schema description. The description compensates by explaining that messages controls how much of the thread is returned, with a default of 5 and a maximum of 20. The ticket format (SUP-42 or id) is also restated with an example, aligning description and 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 precisely that it returns a single support ticket looked up by number (e.g. SUP-42) or id, and enumerates the fields returned. The singular 'one support ticket' plus the number/id key makes it distinguishable from a listing tool without opening either 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?

Gives concrete example user utterances («що в тікеті SUP-42», «що відповів клієнт») that establish the trigger conditions. It does not explicitly name an alternative such as ticket_list for discovering tickets, so the when-not guidance is absent.

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