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

Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description adds genuinely new context beyond that: returned fields (prices, free/paid status, style tags), the preview_url that renders the user's own text, and the licensing fact that all fonts carry a commercial license.

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 tight sentences with the purpose front-loaded and return details trailing, which is the right ordering. It loses a little by restating the schema's query examples verbatim rather than using the space for new information.

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?

With no output schema, the description correctly shoulders the burden of explaining return values (prices, free/paid flag, style tags, preview_url) and license terms. It does not mention result limits, pagination, or what an empty result looks like, a minor gap for a catalog search.

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%, and the description's query examples ('script', 'serif', 'display', 'handwritten', 'wedding invitation', 'logo') simply repeat the schema's own examples. It adds no syntax, format, or default detail beyond the schema, so the baseline 3 applies.

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 gives a specific verb+resource (find fonts in the EpicPxls catalog) and scopes it by the three query axes: name, style, and use. It is clearly a font-domain search, but it never distinguishes itself from the generic sibling search_items, so an agent must infer the boundary.

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?

It implies usage by listing valid query types and mentioning free_only indirectly, but offers no explicit when-to-use or when-not-to-use guidance and names no alternative tool. With search_items and get_item among its siblings, an agent gets no routing help.

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