WhatsApp Business MCP

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

With no annotations provided, the description carries the full burden. It successfully clarifies that this performs a rules-based validation without side effects ('before submitting'), and describes the output ('Validation result with any errors found'). Could be improved by explicitly stating this is a safe, read-only operation with no rate limit consumption.

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?

Well-structured with clear sections (purpose, usage, Args, Returns). Every sentence provides distinct value: the first defines scope, the second establishes workflow, and the Args/Returns sections document parameters. No redundancy 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 complexity (6 parameters including nested array objects) and complete lack of schema descriptions, the description provides comprehensive coverage. Despite the existence of an output schema, the brief Returns summary adds useful context about error-focused output without being redundant.

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?

Excellent compensation for 0% schema description coverage. The Args section provides rich semantic context for all 6 parameters: format constraints for 'name' (lowercase, underscores), valid values for 'category' (MARKETING/UTILITY) and 'template_type', examples for 'language', and structural guidance for 'components' (HEADER, BODY, FOOTER, BUTTONS).

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 (validate), target resource (WhatsApp template), and validation criteria (against Meta's rules). The phrase 'before submitting' effectively distinguishes this from the sibling create_template tool.

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?

Explicitly states when to use the tool ('before creating a template') and establishes the workflow relationship with sibling tools. The guidance 'Use this to check for errors' clearly indicates this is a pre-flight check versus the actual creation/submission.

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