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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety bar is met. The description adds genuinely useful context beyond them: it clarifies this is a transformation rather than a validator, and warns that output 'may normalize formatting, so inspect output before production use' – mutation-adjacent behavior the annotations do not convey.

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?

Four sentences, front-loaded with the core action and capped by a concrete constraint. The second sentence partially restates the first ('Use to compact small JSON, JSONL or CSV samples'), but the remainder earns its place with sibling routing and the output warning.

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?

With no output schema, the description responsibly summarizes the return ('an optimized dataset representation'), and annotations carry the safety profile. Combined with the normalization caveat and sibling routing, an agent has what it needs, though it does not describe error behavior on invalid input.

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 both parameters (input length limit, format enum) are already fully documented in the schema. The description's 'max 4096 input characters' merely repeats the schema constraint and adds no format-selection nuance, so baseline 3 applies.

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 ('Clean or minify JSON/JSONL/CSV data') with an explicit boundary ('Transformation tool, not a boolean validator') and names the sibling it is not (is-json-safe). An agent can distinguish it from both the validity-check family and the other minify siblings without opening a schema.

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?

Gives clear when-to-use ('compact small JSON, JSONL or CSV samples') and an explicit alternative for one case ('For ordinary JSON validity checks, use is-json-safe'). It does not address routing against the other minify siblings (is-minify-js/css, is-prompt-minify), though those cover different formats, so the gap is minor.

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