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

There are no annotations, so the description carries the burden. 'The body is discarded' adds a useful behavioral guarantee that the input is not retained and the operation is non-mutating, but it does not disclose what the tool returns for valid versus invalid JSON or whether it throws.

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 extremely concise: two short sentences with the action first and a meaningful side-effect note second. There is no filler or redundant explanation.

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?

With no output schema and no annotations, the description should state what the agent can expect back from the check and which parameter carries the body. It only says the body is discarded, leaving return semantics and the role of the many other parameters unexplained.

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?

The input schema already provides descriptions for all seven properties, so the baseline is met. The tool description adds little parameter meaning beyond mentioning a discarded 'body' and does not clarify how 'body' maps to the `json` parameter or why fields like `city`, `host`, and `feed` appear.

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 clear action and resource: 'Check whether a body is valid JSON.' This distinguishes the tool from URL, file, and domain shape checkers by focusing on JSON syntax. However, 'body' is slightly ambiguous and the description does not explicitly tie it to the `json` parameter.

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?

Usage is implied: use this tool when you need to verify whether some text is valid JSON. There is no explicit when-not-to-use guidance or reference to sibling alternatives such as file-path-ok or domain-shape, so an agent gets only implicit context.

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