mcp-whatsapp

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

Annotations already indicate this is a destructive, non-idempotent, open-world mutation (readOnlyHint: false, destructiveHint: true, idempotentHint: false, openWorldHint: true). The description adds minimal behavioral context beyond this - it confirms it's a change operation but doesn't elaborate on side effects, permissions needed, or error conditions. No contradiction with annotations exists.

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, efficient sentence that communicates the core purpose without any wasted words. It's appropriately sized for a straightforward mutation tool and gets directly to the point with clear subject-verb-object structure.

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 destructive mutation tool with comprehensive annotations but no output schema, the description provides the basic 'what' but lacks important context about outcomes, error handling, or relationship to sibling tools. While annotations cover safety profile, more behavioral detail would be helpful given the destructive nature.

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 100% schema description coverage, both parameters are already well-documented in the schema. The description adds no additional parameter semantics beyond confirming this tool changes a 'group's display name', which aligns with the 'name' parameter. This meets the baseline expectation when schema coverage is complete.

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 specific action ('Change'), target resource ('a group's display name'), and provides the exact field terminology ('subject') that distinguishes it from similar tools like 'set_group_topic' or 'create_group'. It precisely communicates what the tool does without ambiguity.

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 no guidance on when to use this tool versus alternatives like 'set_group_topic' (for topic vs name) or 'create_group' (initial naming). It lacks context about prerequisites, permissions, or scenarios where this operation is appropriate versus other group management tools.

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