Chats shared with a user

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds the mutual-membership scope but says nothing about pagination, ordering, or whether the target user must be a known contact, so it sits at the annotated baseline.

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 that states the resource, scope, and relationship in one clause. No filler or redundancy.

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 simple read-only list tool with no output schema and annotations covering safety, the description is adequate on purpose but leaves the parameter formats undocumented. An agent can identify the tool but may guess wrong on the 'user' identifier format.

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 0% for two parameters, so the description must compensate and does not. It does not clarify whether 'user' takes a username, ID, or phone number, nor does it explain the 'limit' cap or default beyond what the schema states.

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?

Specific verb ('list') plus a precisely scoped resource ('groups and channels this account has in common with another user'). This is clearly distinguishable from telegram_list_chats by the 'in common with another user' qualifier, though the description never names that 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?

No when-to-use or when-not-to-use guidance. The phrase 'in common with another user' implies the use case but the description offers no prerequisites, no alternatives, and no conditions for choosing this over telegram_list_chats or telegram_full_user.

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