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

No annotations exist, so the description must carry the behavioral burden. It does disclose one non-obvious trait: the body is discarded after the check. But it does not say what the tool returns (boolean, error messages) or how validation failures are surfaced, which is essential for an agent using it.

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 short sentences with no filler and the core action front-loaded. The phrase 'body is discarded' earns its place as a behavioral disclosure, though naming the `json` parameter would improve clarity.

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 output schema and no annotations, so the description must explain return/results and input expectation on its own. It mentions a body but the input schema has nine optional string parameters, and it is unclear how to supply the JSON to validate.

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 baseline is 3; each parameter has a description. The tool description itself adds no parameter-level meaning and never maps 'body' to the `json` property, though the schema's `json` description compensates somewhat.

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 check verb and target resource ('valid JSON'), which distinguishes it from sibling shape validators. However, it refers to 'a body' without tying it to the actual `json` parameter, leaving some ambiguity about what exactly is validated.

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?

Provides no guidance on when to choose validate-json over siblings, nor any conditions or exclusions. There is no mention of alternatives or use cases beyond the one-line task.

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