Check Online Status and Activity of User

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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=true, so the closing 'Read-only operation.' sentence merely restates structured data. The description adds no new behavioral context such as rate limits, privacy/last-seen visibility caveats, or how the multi-account fan-out described in the schema affects results.

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?

Three tight sentences, front-loaded with the resource and what is retrieved, then usage, then safety. The final sentence is redundant with the annotations, which is the only wasted line.

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 an output schema present, the description need not explain return values, and it covers purpose and timing adequately. The only unaddressed nuance is the multi-account fan-out behavior, which the schema itself documents, so no critical gap remains.

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%, with both user_id (numeric ID, @username, or phone) and account fully documented in the schema. The description adds no meaning beyond that, so the baseline 3 for high-coverage schemas 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?

The description gives a specific verb and resource ('Check the online presence, last seen status, and bot flags for a specific Telegram user'), so the agent knows exactly what data comes back. It is clearly distinct from nearby siblings like get_me or get_last_interaction, but it never names an alternative to route against, so sibling differentiation is implicit rather than stated.

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?

'Use before messaging to see if user is active' gives a concrete triggering context rather than leaving usage to inference. It stops short of naming alternatives (e.g., get_last_interaction for history) or stating when this tool is the wrong choice, so it falls just short of the explicit when/when-not bar.

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