mcp-whatsapp

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

The description adds valuable behavioral context beyond annotations: it specifies that the tool reads from local cache and works while disconnected, which is crucial operational information not captured in annotations. However, it doesn't address the destructiveHint=true annotation (what gets destroyed?), rate limits, or detailed response format. With annotations covering safety profile, this adds moderate value but leaves gaps in behavioral understanding.

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: the parenthetical operational note comes first, followed by the core purpose and return format. Every sentence earns its place with zero waste. The structure efficiently communicates the most important information first.

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 (10 parameters, no output schema, destructiveHint=true), the description is moderately complete. It covers the operational context (cache/disconnected) and return format, but doesn't address the destructive nature implied by annotations, doesn't explain the 50% undocumented parameters, and provides limited guidance on when to use this specific message retrieval tool versus alternatives. For a tool with this complexity, more completeness would be expected.

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 50% schema description coverage, the description doesn't add specific parameter information beyond what's in the schema. It mentions 'matching specified criteria' and 'optional context' which aligns with parameters like query, chat_jid, and context_after/before, but provides no additional syntax, format, or usage details. The baseline 3 is appropriate given the schema does some documentation work.

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 tool's purpose: 'Get WhatsApp messages matching specified criteria with optional context.' It specifies the resource (WhatsApp messages) and verb (get/filter), but doesn't explicitly distinguish it from sibling tools like 'get_message_context' or 'search_contacts' that might also retrieve message-related data. The parenthetical note about reading local cache adds useful context but doesn't fully differentiate from alternatives.

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 provides implied usage guidance through the parenthetical '(reads local cache; works while disconnected)', suggesting this tool should be used when offline or when accessing cached data is preferred. However, it doesn't explicitly state when to use this versus alternatives like 'search_contacts' or 'get_message_context', nor does it mention any prerequisites or exclusions. The guidance is helpful but incomplete.

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