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

Annotations already indicate idempotentHint=true, readOnlyHint=false, destructiveHint=false. The description adds context that updating credentials is necessary for message sending, but it does not disclose potential side effects like invalidating existing sessions or requiring re-authentication. With annotations covering safety, the description adds moderate value.

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?

Two sentences with zero waste. The first sentence states the action concisely, and the second provides the rationale. Perfectly front-loaded and to the point.

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?

Given that there is no output schema and the tool is a simple credential update, the description covers the basic purpose. However, it could be improved by mentioning what the tool returns (if anything) or confirming that the update is applied immediately. Overall adequate but not comprehensive.

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?

All parameters are described in the input schema (100% coverage), so the baseline is 3. The description merely groups the parameters under the umbrella of 'WhatsApp Business API credentials' and reiterates their importance, but adds no new semantic information beyond the schema.

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 the verb 'Update' and the resource 'WhatsApp Business API credentials'. It also explains the purpose: these credentials are required for sending messages via the WhatsApp Cloud API, which distinguishes this tool from related tools like neuron_send_whatsapp or neuron_sync_whatsapp_contacts.

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 implies that this tool should be used to set up credentials before sending WhatsApp messages, but it does not provide explicit guidance on when to use this tool versus alternatives, nor does it mention prerequisites or when not to use it. No sibling tools directly compete, so the lack of explicit alternatives is acceptable but still leaves room for ambiguity.

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