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

Annotations already declare read-only, idempotent, closed-world behavior, so the description need not repeat safety facts. It adds the useful claims that results are 'real, validated' and that omitting the name returns the index, but leaves out size, pagination, or output-shape context for a lookup tool.

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?

The key claim — validated patterns for looks the basics do not give — is front-loaded, and the fallback behavior is stated last without preamble. The long keyword enumeration is dense but serves as discoverability, though it could be more cleanly structured.

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 single optional parameter with full schema coverage, strong annotations, and no output schema, the description covers what the tool provides and both invocation modes. It is nearly complete, missing only output volume or listing details that an agent might want before calling it blind.

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 coverage is 100% and the schema already explains that name is drawn from the index with examples. The description goes beyond the schema by stating what happens when the optional parameter is omitted ('Without name: the index'), which is genuine semantics the schema does not supply.

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 resource — validated JSON/HTML/CSS recipe patterns — and enumerates the distinct looks it covers, which is more specific than the title alone. It does not explicitly differentiate itself from siblings such as get_template or get_capabilities, so an agent must infer that this is the recipe catalog rather than a generic template fetch.

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 gives one concrete usage rule: without a name you get the index, with a name you get a specific recipe. It never says when to prefer this over get_template or when it is the wrong tool, leaving the main routing decision implicit.

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