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

With no annotations, the description must carry the full transparency burden. It discloses that the tool builds HTML, includes a preview card and pre-filled message, and returns self-contained HTML. However, it leaves 'web and email variants' vague—no parameter controls the variant—and doesn't describe potential external dependencies or defaults.

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?

One dense sentence that front-loads the core function ('Build embeddable Share on WhatsApp widget HTML') and ends with the output type. No filler words; every phrase earns its place.

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 has 8 parameters, no output schema, and no annotations, the description provides a high-level purpose and output, but omits how the 'web and email variants' are selected and offers no usage context beyond a builder. It is minimally adequate but has gaps.

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 100%, so parameters are already well-documented (e.g., 'description' supports bold/italic/strikethrough). The description's 'pre-filled message' adds only minimal extra meaning, so a baseline score of 3 is appropriate.

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 uses a specific verb 'Build' with a clear resource 'embeddable Share on WhatsApp widget HTML' and specifies the output ('Returns self-contained HTML'). This clearly distinguishes it from siblings like generate_whatsapp_link, which produce links rather than widget markup.

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 through 'embeddable' and 'web and email variants', suggesting it's for embedding share buttons, but it never explicitly states when to choose this tool over generate_whatsapp_link or when not to use it. No alternatives are named.

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