search_fonts

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

With no annotations provided, the description carries the behavioral burden itself. It adds value beyond the schema by stating that results are sorted by popularity and that at least one search criterion is required. It does not spell out the result shape, but for a read-only search tool that is a minor omission.

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, purposeful sentences with no filler. Every sentence contributes either the operation, a behavioral detail, or a usage constraint.

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 search with fully documented parameters, the description is mostly complete: it covers search dimensions, sort order, and the minimum-input rule. The only real gap is not describing the return format, but the absence of an output schema makes this a minor, not critical, omission.

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?

The schema already describes each parameter, so the baseline is 3. The description earns a 4 by adding a key inter-parameter constraint: query and category can be used together or alone, but at least one is mandatory. This is not encoded in the required-parameters list, making it genuinely useful.

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 names a specific verb ('Search'), resource ('Google Fonts'), and criteria ('family name and/or category'). This clearly distinguishes search_fonts from sibling tools like get_font_details, preview_text, and get_embed_code.

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 clearly states the input requirement that at least one of query or category must be provided, which is useful. However, it does not explicitly say when to prefer this tool over its siblings or when not to use it, so routing guidance is only implied by the tool's purpose.

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