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

Annotations already establish readOnly, idempotent, and non-destructive, lowering the bar. The description still adds genuinely useful behavior: it is free, requires no key, and the badge refreshes itself from delivered/paid orders and links back to the shop. It stops short of describing format/pagination details, but that is minor here.

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?

Three short sentences, front-loaded with the 'Seller:' audience and the resource, followed by value, behavior, and cost. Every clause carries information; only the somewhat parenthetical '(SVG plus ready markdown and HTML)' is optional detail.

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 simple read-only getter with no output schema, the description covers what is produced (badge artifact plus markdown/HTML), how it stays current, and the cost/auth posture. The only real gap is the undocumented required parameter.

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?

There is one required parameter (agent_id) with 0% schema description coverage, so the description carries the full explanatory burden -- yet it never mentions the parameter at all. An agent must infer the identifier's meaning from the property name alone.

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?

States a specific verb and resource: a live 'Word Pass badge' delivered as SVG plus ready markdown/HTML, auto-updating from delivered paid orders. This is concrete enough to distinguish it from neighbors like get_pass or prove_word_pass, though the description never explicitly names a sibling to differentiate against.

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?

Usage is implied by the audience and placement note ('Seller: ... for your website or README'), which tells the agent the intended context. However, there is no explicit when-to-use vs. when-not guidance and no alternative tool is named among the many Word Pass siblings.

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