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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is fully covered elsewhere. The description adds nothing beyond that — no mention of what happens if the ID is unknown, whether the message must belong to the given chat, or the shape of the result.

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 with zero padding. It is efficient but borders on under-specification given the tool's place among 40+ siblings.

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?

With full schema coverage, all-required params and complete annotations, the definition is minimally sufficient to invoke the tool. It stops short of explaining what a returned message contains or what happens on a miss, which matters since no output schema exists.

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% and all three parameters are documented in the schema, so the baseline is 3. The description contributes no extra semantics about the interaction between chat_id and id_message or how the ID is formatted.

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 ("Get a message") scoped by ID, so the agent can tell it retrieves a single message rather than a list. It offers no differentiation from siblings that also return message content, such as whatsapp_get_chat_history or whatsapp_last_incoming_messages.

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 tool versus the many message-reading siblings, and no prerequisites or exclusions are stated. The agent must infer from the name alone that this is for fetching one known message ID.

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