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

Beyond the readOnly annotation, the description explains the return shape and important behavioral consequences: when connected is false, broadcasts are only previews, and when health.ok is false, the number may be connected but every send will fail. This is exactly the kind of context an agent needs before deciding whether to proceed with a broadcast.

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 front-loaded with the core purpose, then adds the return fields and the critical delivery/health caveats. Despite being multi-sentence, every sentence carries operational value and there is no filler.

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?

There is no output schema, but the description documents the meaningful return fields and their implications. Combined with the annotations and the absence of parameters, it gives the agent everything needed to call the tool and interpret the result correctly.

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 tool has zero parameters, so there is no parameter semantics to document. The schema coverage is 100% and the description does not need to compensate for any missing parameter details; the baseline for a parameterless tool 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 clearly states a specific verb and resource: checking whether the workspace has a connected WhatsApp number. It also distinguishes this status check from related actions like send_broadcast and whatsapp_connect_link, so an agent can identify its role among siblings.

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?

It explicitly says to call this before send_broadcast when real delivery is expected, and to use whatsapp_connect_link when not connected. It also gives a clear rule for the health failure case: read health.message and health.remediation and do not resend until fixed.

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