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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does reveal one side effect: 'The body is discarded,' indicating the input is not retained. However, it never states what the tool returns, whether validation is syntax-only, whether errors are reported, or how the `json` parameter relates to the 'body.' With no output schema, these details are important.

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 description is only two sentences with the purpose front-loaded and the key side effect stated second. There is no filler or repetition. This is an appropriately concise structure for a simple validation tool.

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?

The tool has no annotations and no output schema, yet the description omits the return contract and how to map inputs to the nine-parameter schema. The eight non-json parameters are especially unaddressed, leaving an agent unsure which parameters are relevant. The description is too minimal for the actual schema and context.

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%, so the baseline is 3 even though the tool description adds no parameter detail. The schema itself describes `json` as 'JSON text to validate,' but the description calls the input a 'body,' creating some ambiguity. The eight other parameters are each described in the schema, but their relevance to JSON validation is unexplained by the description.

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 states a specific verb and resource: 'Check whether a body is valid JSON,' which clearly distinguishes it from sibling shape/URL/status checkers. However, it does not map the 'body' to the actual `json` parameter in the schema, and the schema also lists eight other unrelated optional parameters. The high-level purpose is clear, but the input target is not fully precise.

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?

There is no guidance on when to use validate-json versus alternatives such as domain-shape, file-path-ok, or browser-url-ok. The description gives no explicit conditions, exclusions, or alternative tool names. The only hint is the name and the generic phrase 'body,' so the agent must infer the use case.

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