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

Annotations already declare destructiveHint=true, idempotentHint=true, and openWorldHint=true, covering the safety profile. The description adds nothing beyond that: it doesn't say whether removed participants are notified, whether non-members cause errors, or whether removal is partial on failure. With annotations carrying the load, the description still contributes no extra behavioral context.

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 with zero waste and the verb-resource structure stated immediately. It is arguably under-specified rather than over-verbose, but structurally clean.

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-required-parameter destructive mutation with no output schema and only 50% schema coverage, the description is too thin. Even with annotations covering safety, an agent lacks guidance on prerequisites, error/partial-failure behavior, and the semantics of the undocumented parameters.

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 only 50% (group_id and phone_numbers are undocumented), so the description must compensate and it does not. It mentions phone numbers but adds no format, cardinality, or constraint details, leaving half the parameters unexplained anywhere.

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 ('Remove') and resource ('phone numbers from a WhatsApp group'), so the operation is unambiguous. However, it does not distinguish itself from the obvious sibling whatsapp_group_participants_add, which an agent must be steered away from when the intent is removal, nor does it clarify bulk vs single removal.

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?

There is no when-to-use guidance, no mention of prerequisites (e.g., the number must currently be a participant, admin requirements), and no reference to the add counterpart. The agent gets no routing help beyond the name itself.

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