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

Annotations already declare readOnly=false, destructive=false, idempotent=false, and the description adds one genuinely useful fact beyond them: credentials are removed from the session. It does not say whether the instance record survives, whether reconnect is required to restore service, or whether in-flight messages are affected — the practical questions for an agent calling a non-idempotent session operation.

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 tight sentence with the action front-loaded and the credential-removal consequence appended. No filler, nothing to trim.

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 one-parameter, no-output-schema tool with annotations covering the safety profile, the definition is minimally adequate. The missing piece is sibling disambiguation against whatsapp_logout and whatsapp_delete_instance, which is the main way an agent could misuse this tool.

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?

Only one parameter, instance_id, and the schema already documents it at 100% coverage. The description adds no format, sourcing, or validity detail (e.g. how to obtain the ID via whatsapp_get_instances), 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?

States a specific verb and resource ("Disconnect a WhatsApp instance") plus the side effect of removing session credentials, so the action is unambiguous. However, it offers no differentiation from close siblings like whatsapp_logout, whatsapp_delete_instance, and whatsapp_connect, which an agent must distinguish before choosing.

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 guidance on when to use this instead of whatsapp_logout (also a session-terminating operation) or whatsapp_delete_instance (which presumably also invalidates the instance). No preconditions, no exclusions, and no statement about what happens to the instance record afterwards.

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