Get a chat

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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lowered, yet the description adds genuine behavioral semantics beyond them: a missing state field means 'unknown', not `false`, and a chat with no stored message yields a `not_found` result. These are real disclosure points an agent needs.

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 resource and scope, then adds the unknown-vs-false caveat and the not_found behavior in compact form. The final sentence ('A chat wuapi stored no message of answers `not_found`') is grammatically awkward, slightly reducing clarity, but no padding is present.

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 carries the return-value burden and does so by enumerating the relevant fields, the unknown-field semantics, and the failure case. It is largely complete for a single-item read; pagination/format detail is not applicable here.

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 both parameters (accountId, chatId) are richly documented, including chatId formats. The description adds no parameter-level detail beyond the schema, so baseline 3 is appropriate.

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: retrieves one conversation and enumerates what it returns (name, latest message in full, unread/pinned/archived/muted state). The phrase 'One conversation of an account' distinguishes it from the collection-oriented sibling list_chats, though it does not name the sibling 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?

Usage is implied rather than stated: it retrieves a single chat, and the note that a chat with no stored message answers `not_found` gives a useful edge-case context. However, there is no explicit when-to-use versus get_message/list_chats/get_group, nor any prerequisite guidance beyond what the schema provides.

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