list_chats

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

Annotations already declare readOnlyHint=true, so the description's mention of reading local cache is additive, clarifying that the tool does not require network access. This provides useful context beyond the annotations, aligning with behavioral expectations.

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 a single, front-loaded sentence with the most critical behavioral note (offline capability) in parentheses. Every word is necessary and no extraneous information is present.

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?

The tool has 5 parameters, no output schema, and a simple purpose. The description covers the offline behavior and basic intent, but lacks details on pagination, return format, or how criteria matching works, which are needed for full understanding given the parameter count.

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 only 40% (query and sort_by have descriptions). The tool description does not elaborate on parameters like limit, page, or include_last_message, leaving their semantics unclear. The description only vaguely references 'matching specified criteria', failing to compensate for the parameter documentation gap.

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 it retrieves WhatsApp chats matching criteria, and the parenthetical note about reading local cache distinguishes it from network-dependent tools. The name 'list_chats' is self-explanatory, but it does not explicitly differentiate from sibling tools like 'list_groups' or 'get_chat'.

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 indicates it works offline by reading local cache, implying it is suitable for disconnected use. However, it provides no guidance on when not to use it or alternatives (e.g., for groups or individual chats), leaving the agent to infer based on sibling names.

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