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

Goes far beyond the read-only/open-world annotations by disclosing the return contract (valid yes/no, error paths, sanitized value), unsupported keyword behavior (returns error instead of silently passing), and payment semantics including that failed calls are not charged.

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?

Front-loads the core operation, then packs supported keywords, return behavior, unsupported-feature behavior, and pricing into a compact block. The keyword list is long but earns its place by defining the validation boundary.

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?

Complete enough for an agent to call correctly: purpose, supported keyword set, return shape, limitations, and payment model are covered. The output schema exists, so return-value detail is supplemental rather than required, and no major gap remains.

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 the input schema already documents that 'value' is any JSON and 'schema' is the JSON Schema. The description reinforces the schema context but adds no syntax, formatting, or parameter-specific meaning beyond the structured fields.

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?

States a specific verb and resource: checks an agent's JSON output against a JSON Schema. It also names the supported draft and keyword set, distinguishing clearly what the tool validates.

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?

Implies use for JSON Schema validation and explicitly lists which schema keywords are supported and which unsupported features will return an error. It does not name alternative sibling tools or when-not-to-use cases, but the supported/unsupported boundary is clear.

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