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

Annotations already communicate destructiveHint=true, readOnlyHint=false, and idempotentHint=false. The description is consistent with those and adds the specific behavioral scope (group leave vs. channel unfollow), but it does not add further context such as irreversibility, admin requirements, or side effects on messages/membership.

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 states the action, the target resource types, and the key parameter concept. There is no filler, repetition, or unnecessary detail.

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 two-parameter tool with a full input schema, a destructive annotation, and an output schema present, the description covers the essential semantics. Nothing an agent needs to invoke 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 description coverage is 100%, with jid and account_id both documented clearly. The description's mention of 'by its JID' and 'one of your accounts' loosely maps to the parameters but adds no real semantic value beyond what the schema already provides, so the baseline of 3 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 uses a specific verb-resource pairing: 'leave a group or unfollow a channel' on 'one of your accounts', and it explicitly names the addressing mechanism ('by its JID'). This clearly differentiates it from siblings like wa_create_group, wa_join_group, wa_delete_group, and wa_follow_channel.

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?

The scope is clear: use when leaving a group or unfollowing a channel. However, it does not explicitly state when not to use it or mention alternatives such as wa_join_group or wa_follow_channel for the reverse operation. The usage context is implied rather than directly contrasted with siblings.

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