mcp-whatsapp

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

The description adds valuable context beyond annotations: it specifies that the tool reads from a local cache and works while disconnected, which clarifies its operational constraints. Annotations provide hints (e.g., destructiveHint: true, openWorldHint: true), but the description doesn't contradict them and enhances understanding of the tool's behavior in offline scenarios.

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 extremely concise and front-loaded, using only two sentences that efficiently convey the tool's purpose and key behavioral trait. Every word earns its place, with no redundant information or fluff.

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's complexity (5 parameters, no output schema) and annotations, the description is adequate but incomplete. It covers the offline behavior and purpose but lacks details on return values, error handling, or how parameters interact, leaving gaps for an AI agent to infer usage.

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?

With schema description coverage at 40%, the description doesn't add parameter-specific details beyond the schema. It mentions 'matching specified criteria', which aligns with the 'query' parameter but doesn't explain other parameters like 'limit' or 'sort_by'. The baseline is 3 since the schema covers some parameters, but the description doesn't fully compensate for the low coverage.

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 ('Get') and resource ('WhatsApp chats') with the specific scope of matching criteria, distinguishing it from siblings like 'list_groups' or 'list_messages'. However, it doesn't explicitly differentiate from 'get_chat' or 'search_contacts', which slightly reduces specificity.

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 usage context with '(reads local cache; works while disconnected)', suggesting this tool is for offline scenarios. However, it lacks explicit guidance on when to use this versus alternatives like 'search_contacts' or 'get_chat', and doesn't mention exclusions or prerequisites.

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