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

The description only notes that 'The body is discarded,' implying non-destructive behavior. With no annotations, this is insufficient—it does not clarify that only the 'json' parameter is relevant and others are ignored, nor does it mention any side effects, authentication, or error handling. The agent lacks crucial behavioral context.

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 concise (one sentence) but poorly structured: it does not front-load the essential parameter ('json') or provide any prioritization. It is short but not helpful, failing to guide the agent on what matters most.

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 9 parameters and no output schema, the description is severely incomplete. It does not explain which parameter to pass, what the expected input format is, or what the return value represents (e.g., boolean, error). An agent cannot reliably invoke this tool without additional inference.

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 parameters are documented, giving a baseline of 3. However, the description introduces ambiguity by using 'body' instead of the actual 'json' parameter, and does not add any value beyond the schema—it actively confuses the mapping. Thus, it falls below baseline.

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 ('Check whether a body is valid JSON') with a specific resource (JSON validity). However, the term 'body' is ambiguous and does not map to any parameter in the schema (which has 'json'). It distinguishes itself from sibling tools by mentioning JSON, but lacks specificity about which input to use.

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 alternatives, no mention of context, prerequisites, or exclusions. The single-sentence description provides no usage direction, leaving the agent to infer when this tool is appropriate.

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