get_online

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

The description implies a read operation but does not disclose any behavioral traits like permissions, rate limits, error handling, or what happens with invalid IDs. Since no annotations are present, the description should cover these aspects.

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 description is a single, concise sentence that effectively communicates the core action and constraint (up to 100 users). No unnecessary words; it is front-loaded and efficient.

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?

Given the tool's complexity (only one parameter, no output schema, no annotations) and the presence of many sibling tools, the description is insufficient. It omits return values, error handling, and when to use, making it incomplete for adequate agent understanding.

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?

The schema has 100% parameter description coverage, so baseline is 3. The description adds minor context by stating the purpose (online status), but the parameter description already specifies 'Viber user IDs'. No significant new meaning beyond the schema.

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 clearly states the action ('check') and the resource ('online status of up to 100 Viber users'). It distinguishes this tool from siblings like 'get_user_details' or 'send_message' which serve different purposes.

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 guidance is provided on when to use this tool versus alternatives, such as when to check online status vs. using other tools. The description lacks context for decision-making.

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