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

With no annotations, the description carries the full burden of behavioral disclosure. It does add a useful privacy note ('No identifiers are retained'), but it leaves the core behavior obscure: what 'classified' means, what output is produced, and whether any external access or side effects occur. The schema already notes that most values are discarded, so the description adds only a global retention guarantee.

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 short sentences with no filler, and the primary action is front-loaded. It sacrifices helpful precision for brevity, but as far as sheer conciseness and structure go, it is effective.

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?

Given a high-complexity signature (9 optional parameters, no required parameters, no output schema, no annotations), the description is far too thin. It does not explain how a request is classified, what the agent should expect in return, which parameters are appropriate in which situations, or how this tool relates to its siblings.

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%, and each parameter has its own meaningful description (e.g., 'discarded after the shape check', 'no disk access'). The description itself adds no parameter-level semantics, so the schema carries the load. No aggregation guidance is provided about whether parameters are mutually exclusive or how they map to the classification.

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 verb and object ('Show how this request is classified'), so it is not a tautology, but 'classified' is vague and never tied to the tool name 'compatibility' or to any classification scheme. It does not distinguish the tool from the many sibling tools that also accept URLs, file paths, queries, or JSON.

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?

No guidance is given about when to call this tool versus alternatives like validate-json, domain-shape, or status-catalog. There are no exclusions, no prerequisites, and no hint about which of the nine optional parameters should be supplied.

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