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

With no annotations, the description must carry the behavioral burden. It does disclose that the body is discarded, indicating the input is not retained, but it does not state whether the operation is strictly read-only, how invalid JSON is reported, or what error behavior to expect.

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 declarative sentences, front-loaded with the core purpose and followed by one behavioral note. No filler, repetition, or tangential detail.

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 seven parameters, a fairly generic name amid several sibling validators, and no output schema or annotations. The description does not cover which parameter(s) to supply, what the result looks like, or when this tool is preferred, so it is incomplete for an agent deciding how to invoke it.

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?

All seven parameters have descriptions in the input schema, so the schema already explains each field. The description adds no parameter-level meaning beyond repeating that the body is discarded; the relationship of parameters like city/feed to JSON validation remains undocumented.

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 opens with a specific action and resource: 'Check whether a body is valid JSON.' It clearly identifies the core operation, though the term 'body' is slightly ambiguous and it does not say what result is returned. It is clear enough but lacks the sharp differentiation a 5 would require.

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 about when to use validate-json instead of sibling validators such as domain-shape, file-path-ok, or browser-url-ok. No exclusions, prerequisites, or alternative routing are mentioned.

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