Format or Minify JSON

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds value by disclosing error behavior ('precise error location when it is invalid') and a guarantee ('it cannot drop or alter a value'), which are not in the annotations. This is useful context beyond the structured fields.

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 sentences with no filler. The core purpose is front-loaded, followed by a usage preference and a link. Every sentence earns its place, and the structure is efficient.

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 simple formatting tool with annotations covering safety and a schema for parameters, the description is nearly complete. It mentions error location, which is a return behavior, and implies the output is formatted JSON. It does not explicitly state the return value, but that is easily inferred. A small gap, but not a significant one.

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% (json and sortKeys have descriptions; mode and indent do not). The description does not compensate for the missing parameter details – it only mentions 'pretty-print or minify' which relates to mode but does not explain indent or explicitly map the parameters. It adds minimal value beyond the schema and fails to bridge the coverage gap.

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 ('pretty-print or minify') and resource ('JSON'), and adds a distinguishing capability ('precise error location'). It is clear and unambiguous, and no sibling tool performs JSON formatting, so it stands apart.

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?

It gives explicit guidance: 'Prefer this to reformatting a large document yourself' – this tells the agent when to use it. It does not name an alternative tool, but none exists among the siblings, so the context is sufficient. It could be stronger with explicit 'do not use when...' but it is clear.

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