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

With no annotations provided, the description carries the full disclosure burden. It does disclose a meaningful behavioral trait — 'The body is discarded' — which informs the agent that the input is not stored or returned. However, it does not disclose the output behavior (e.g., boolean result, error on invalid JSON, or parsed output), which is essential for a validation tool with no output schema.

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 sentences, front-loaded with the core purpose and immediately followed by the key behavioral caveat. Every word earns its place; there is zero filler or redundancy.

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?

Despite 100% schema coverage, the tool has 9 parameters, no annotations, and no output schema. The description leaves critical context unaddressed: what the tool actually returns, how invalid JSON is signaled, and why eight seemingly unrelated parameters exist. An agent cannot fully predict the tool's behavior from this description alone.

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 baseline is 3. The description's 'body is discarded' statement adds a general semantic that the per-parameter 'discarded' annotations already convey. It contributes no param-specific meaning beyond what the schema documents, so it neither compensates for gaps nor degrades the picture.

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 specific verb and resource ('Check whether a body is valid JSON'), which clearly conveys the tool's function and is self-evidently distinct from shape-check siblings like domain-shape and file-path-ok. However, it does not explicitly differentiate itself from sibling tools or explain why the schema accepts 8 unrelated parameters, so it stops short of a 5.

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 description implies the usage context — invoke when you need to determine if a body is valid JSON. It provides no explicit when-to-use or when-not-to-use guidance, no mention of alternatives among the many sibling validation/shape tools, and no clarification that the other parameters are irrelevant decoys.

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