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

With no annotations provided, the description carries the full behavioral burden, and it does disclose one meaningful trait: the body is discarded after the check. However, it omits important behavior such as what the tool returns, how invalid JSON is reported, and whether any side effects occur.

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 two short, front-loaded sentences with no filler. The action is stated first, and the disposal behavior is added concisely in the second sentence.

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, yet the description never states what the tool returns or how a valid/invalid result is signaled. It also does not explain which of the nine optional parameters matter for the JSON validation beyond relying on the schema's own descriptions.

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 schema already documents all nine parameters. The description adds the 'body' terminology but does not clarify which schema parameter corresponds to the body, leaving that to the json parameter 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 uses a specific verb ('Check') and a precise target ('whether a body is valid JSON'), making the tool's core purpose immediately clear. It is also distinct from sibling validators like domain-shape or wiki-title-ok, which focus on different input types.

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 purpose implies that the tool should be used when an agent needs to validate whether a body is valid JSON, but it gives no explicit when-to-use or when-not-to-use guidance. It does not name alternative tools or exclude scenarios.

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