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

Despite no output schema, the description fully describes the return shape: JSON-LD as data and inside a script tag, plus required fields left empty, invalid values detected (zero price, non-ISO currency, partial hours), recommended fields omitted, and the field map per type. It also confirms the no-fetch behavior, consistent with readOnlyHint and openWorldHint=false.

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 purpose is front-loaded, but the middle is a long run-on sentence whose embedded return-value list ('the required fields left empty, what is not right..., the recommended fields left out...') is grammatically tangled and slow to parse.

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 3-param generator with no output schema and nested object input, the description covers types, input conventions, return contents, and validation behavior. Only the exact textual format of the returned field listing is left fuzzy.

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%, so the schema already documents all three parameters, setting a baseline of 3. The description adds useful semantics for 'type' alone (discovery mode) and for 'fields' (empty values are dropped, not invented), but nothing beyond that for 'as'.

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 artifact: 'Makes JSON-LD for one page from the fields given,' then enumerates the supported types. 'Fetches nothing' and the explicit exclusion of FAQPage/HowTo pin down the scope so there is no ambiguity about what it produces.

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?

Gives concrete procedural guidance: 'Call it once with only "type" to see the fields' and 'Give only values the page shows.' It also explains the exclusion rationale (Google no longer shows FAQPage/HowTo). It doesn't name a sibling alternative, but no sibling overlaps this generate-schema job.

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