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

Beyond the annotations, the description discloses the send gate (OFF by default, no tool flips it, text only, no media/buttons), the permission requirement, the live-read cost (large accounts up to a minute), idempotency behavior (existing contacts untouched), and the watched-groups non-effect. These are exactly the operational traits annotations cannot express.

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?

The purpose and the send-gate caveat are front-loaded, and every sentence carries information. It is a dense single paragraph, though, and the constraint clauses (permission, sending limits, idempotency, watched-groups) could be separated for faster scanning.

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 4-parameter mutation with no output schema, the description covers what gets created, what is left alone, the failure conditions, and the permission/auth context. Nothing an agent needs in order to call it correctly 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%, so the baseline is 3, but the description adds a concrete narrowing example (["group","channel"] to exclude personal DMs) and reiterates the single-userbot omission rule for botId. It does not add anything about limit or applicationId beyond the schema, so it exceeds baseline only modestly.

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?

The description states a specific verb and resource ('Import a telegram_mtproto userbot's existing chats as contacts') and enumerates exactly which dialog kinds are imported (DMs, groups, channels). It clearly distinguishes this bulk-import from single-record siblings like create_contact and list_contacts by describing the live dialog-list read and the idempotent 'creates missing contacts' semantics.

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?

It states when to reach for this tool (so existing chats become contacts send_message can target without waiting for an inbound message), what it explicitly does NOT do ('Does NOT change the watched-groups list'), the prerequisite (manage_broadcasts permission, userbot connected), and the downstream constraint (sending stays rejected until the dashboard toggle is on). An agent has enough to decide for or against it.

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