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

The description adds meaningful behavioral detail beyond the annotations: it explains the preview/confirm flow, states that chats remain on the phone, and warns that WhatsApp tools will stop working after disconnection. This aligns with the readOnlyHint=false and destructiveHint=false annotations and gives the agent a complete safety picture.

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 sentences, each earning its place: the main action and scope, the safety guarantee, and the confirm behavior. The critical preview/confirm nuance is front-loaded and clearly separated, making the description easy to parse quickly.

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 single-parameter tool with an output schema and annotations covering safety, the description is complete: it covers what happens on disconnect, the confirm workflow, the effect on other WhatsApp tools, and how to reverse the action. Nothing needed to invoke the tool 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?

The schema already fully documents the single confirm parameter with the same semantics ('Must be true to actually unlink. Without it, returns a preview'). The description repeats this rather than adding new meaning, so the baseline score of 3 for full schema coverage 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 states a specific verb and resource: 'Unlink WhatsApp from Local MCP' and 'logs out the linked device on this Mac (via wacli)'. This clearly distinguishes it from related tools like whatsapp_connect and other WhatsApp operations by scoping the action to unlinking this specific Mac.

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 description gives clear usage context: it is for disconnecting this Mac, and it notes that WhatsApp tools stop working until whatsapp_connect is run again. While this implies the reconnection alternative, it does not explicitly say 'use whatsapp_connect to reconnect,' so it stops short of a fully explicit alternative-routing statement.

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