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

With no annotations provided, the description fully carries the burden, and it excels: it discloses determinism, CPU-only execution, bounded repair scope, honesty about missing fields (never invented), price via x402, and the crucial side effect that calling returns a checkout contract without executing or charging the caller. This goes far beyond a basic tool summary.

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 two sentences with the core purpose front-loaded. The first sentence states what the tool does; the second adds price and side-effect context. Every sentence earns its place, and there is no fluff or repetition.

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 four parameters, a nested schema object, and no output schema, the description gives essential behavior but leaves gaps: it does not explain the mode enum values, the role of job_id, or what the REST/x402 checkout contract contains. The safety and cost context is strong, but the operational completeness is only partial.

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 50% (text and schema have descriptions; mode and job_id do not). The description adds some parameter-level meaning by noting optional validation (mapping to mode) and the bounded/subset nature of schema validation, but it does not clarify mode enum values or the purpose of job_id. It neither fully compensates for the gap nor leaves it entirely unaddressed.

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 clearly states the tool repairs a bounded set of common JSON syntax mistakes, returns canonical JSON, and optionally validates a JSON Schema subset. This specific verb-resource mapping distinguishes it from unrelated siblings like run_python or scenario_council.

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 provides clear context for use: it is a deterministic CPU-only JSON repair/validation utility. It does not explicitly name alternatives or exclusions, but the sibling tools are unrelated, so the context is sufficient without further routing guidance.

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