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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds valuable context: the data comes from a local store (so may be stale), warns about Wacli being unofficial and potential ToS restrictions. This goes beyond the annotations and helps the agent anticipate risks and freshness.

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: the first states the purpose and usage context (local store, sync hint, JID usage), the second carries the risk warning. Information is front-loaded and every sentence earns its place without redundancy.

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 the tool is a read-only list operation with an output schema, the description covers all essential aspects: what it lists, the data source, prerequisites, how to use the results, and a risk warning. Nothing critical is missing for an agent to call it 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 schema provides 100% coverage for both parameters with clear descriptions (limit max, query filter). The description does not add additional parameter semantics beyond what the schema already states, so the baseline of 3 is appropriate.

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 (lists) and resource (WhatsApp groups this account is in), and mentions the output (JID and name). It distinguishes from chat listing by specifying groups, but does not explicitly contrast with sibling tools like whatsapp_list_chats, so it's clear but not fully differentiated.

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?

Provides explicit guidance to run whatsapp_sync first if a just-created/joined group is missing, and explains how to use the returned JID as chat_id for other tools. This gives clear context for when to use this tool and prerequisites, though it doesn't explicitly state when not to use it.

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