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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful context beyond that: the exact lookup keys (numeric id or @username) and the field set returned, which matters since no output schema exists. It omits what happens on an unknown/inaccessible chat, keeping it from a 5.

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 sentence that front-loads the verb and resource and then the return payload; every clause earns its place with no redundancy or 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?

For a read-only single-parameter lookup with annotations covering safety, the description is nearly self-sufficient: it names the lookup keys and the returned fields, compensating for the absent output schema. The only real gap is error/not-found behavior and rate-limit context.

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?

Only one parameter, and schema coverage is 100% – the schema already documents 'Numeric chat id or @username'. The description restates the same dual-key idea without adding format nuance (e.g. sign of numeric ids, whether @ is required), so the 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+resource (get info for a chat) and enumerates the returned fields (type, title/name, username, description), which separates it from telegram_read_recent_updates and telegram_get_bot_info. It does not explicitly name a sibling, so it lands just short of a 5.

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 'a chat your bot can see' implies the access precondition a caller must satisfy, but there is no explicit when-to-use versus telegram_read_recent_updates or telegram_get_bot_info, and no statement of when this tool is the wrong choice.

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