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

Annotations already establish the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower. The description adds real behavioral content by enumerating exactly what gets checked and which input shapes are accepted, though it says nothing about error/report format or strictness levels.

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?

Two dense sentences, front-loaded with the purpose and condition, then the accepted input forms. No filler and nothing that fails to earn its place.

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?

An output schema exists, so return values need not be described. For a single-parameter, annotation-covered validator, the description supplies everything an agent needs to call it correctly: the trigger condition, the checks performed, and the accepted input shapes.

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% with a single 'jsonld' param, giving a baseline of 3. The description goes beyond the schema by specifying that the input may be a single object, an array, a @graph, or a full <script type="application/ld+json"> block, which clarifies what the text string may actually contain.

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?

Specific verb ('Validate') plus resource ('JSON-LD') with explicit scope: syntax, @context/@type, absolute URLs, ISO dates, and Google's required/recommended fields. An agent can distinguish this from the sibling generate_schema without opening any schema.

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?

The temporal condition 'before you publish it' clearly frames when to reach for this tool. However, it never names the alternative (generate_schema) or states when-not to use it, so routing between the two siblings is left to inference.

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