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

No annotations are provided, so the description must fully disclose behavior. The only behavioral note is 'The body is discarded,' which is a minimal safety disclosure. It does not state whether the tool returns a boolean, throws an error, or what happens on invalid input. There is no mention of side effects, rate limits, or output format, leaving the agent to guess at the tool's behavior.

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—only two short sentences. While it avoids verbosity, it is too under-specified to be genuinely helpful. It does not front-load any critical information beyond the basic purpose, and the 'body is discarded' note is the only additional context. The brevity borders on under-specification rather than effective conciseness.

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?

For a tool with nine optional parameters and no output schema or annotations, this description is woefully incomplete. It does not explain what 'body' means, how the parameters interact, what the return value is, or how errors are signaled. An agent has no way to know whether this tool is appropriate for a given task or how to interpret its result. The description fails to provide the essential context needed for correct usage.

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 every parameter is documented with its own description. The tool description adds no additional meaning beyond what the schema already provides; it merely restates that the body is discarded, which is also noted in the 'json' parameter description. The description does not explain how the other eight parameters relate to the main JSON validation action, but the schema already covers each parameter individually, so a baseline score of 3 is appropriate.

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 verb and resource: 'Check whether a body is valid JSON.' It is specific to JSON validation and distinguishable from sibling tools like 'domain-shape' or 'wiki-title-ok'. However, the term 'body' is ambiguous—it could refer to the 'json' parameter or an HTTP request body—and the description does not clarify which parameter it refers to, nor does it acknowledge the presence of nine other unrelated parameters.

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 this tool versus any alternative. It does not mention any conditions, prerequisites, or exclusions. An agent has no information about when JSON validation is appropriate or how it differs from similar shape-checking siblings like 'domain-shape' or 'file-path-ok'.

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