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

Annotations already mark readOnlyHint false, so the agent knows it's a write, but the description adds no context about mute duration, default behavior, reversibility, or side effects. 'Requires chat_jid' merely restates the schema's required field. No behavior beyond the structured metadata is disclosed.

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 short but not effective: the first sentence is generic filler and the action list is misleadingly broad. The bracket 'Flattened action: mute' is metadata, not user-facing guidance. The only useful clause is 'Requires chat_jid,' which duplicates the schema.

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 3-param mutation tool with no output schema, this description omits the essential mute behavior, duration semantics, and account context. It reads like a generic template rather than a complete tool contract. An agent cannot confidently invoke this tool correctly from the description alone.

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 coverage is 0%, and the description doesn't compensate: it only repeats that chat_jid is required. account and duration_secs are completely unexplained, especially duration_secs which is essential for a mute operation. This gives the agent no parameter semantics beyond field names/types.

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 says 'Change a chat's state' and lists archive/unarchive, pin/unpin, mute/unmute, but it never states that this specific tool mutes a chat. The bracket note 'Flattened action: mute' is the only mute-specific signal. It does not distinguish from sibling tools such as whatsapp_chat_archive or whatsapp_chat_pin.

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?

No when-to-use guidance is provided; it doesn't say to prefer this for muting instead of archive/pin/etc. The generic action list could mislead an agent into thinking this tool can perform multiple state changes. No alternatives or exclusions are mentioned.

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