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

With no annotations, the description carries the full burden of explaining behavior, but it only mentions that identifiers are not retained. It does not state whether the tool performs read-only checks, how it processes inputs, or what side effects (if any) exist. The classification logic is entirely opaque.

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 a single, concise sentence with no unnecessary words or repetition. It is well-structured and directly states the core function, even if that function is under-specified.

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 the complexity of 9 parameters and the absence of an output schema, the description is severely incomplete. It fails to explain what the classification result looks like, how the parameters interact, or what inputs are required for specific outcomes. An agent would have no way to predict the tool's behavior.

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?

Each parameter has a description, and the schema coverage is 100%. However, the descriptions are minimal and do not clarify how each input contributes to the classification. For example, 'discarded after the shape check' implies a validation step but does not explain the relationship between parameters.

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 says 'Show how this request is classified' but does not specify what kind of classification is performed or what the output represents. The tool name 'compatibility' hints at a purpose, but the description alone is too vague to understand the tool's core function.

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?

There is no indication of when to use this tool versus any of the many sibling tools. The description provides no conditions, examples, or context that would help an agent choose this tool over alternatives like validate-json or normalize-url.

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