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

With no annotations, the description carries the full burden of disclosing behavior. It does add a meaningful privacy guarantee ('No identifiers are retained') and the schema descriptions reinforce that values are discarded after checks. However, it does not disclose what the classification output looks like, whether any external network activity occurs, or whether the operation has side effects beyond classification.

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 concise: two short sentences with no redundant wording. The main action is front-loaded in the first sentence, and the privacy note is delivered efficiently in the second. It could earn a 5 if the first sentence were more informative about the classification output.

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 nine optional parameters, no annotations, and no output schema, the description is too incomplete for an agent to know how to invoke this tool correctly. It lacks the classification categories, required versus optional inputs, and expected response format. The privacy note is useful but does not compensate for the missing operational context.

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 the baseline is 3 because each parameter is already documented with its purpose and discard behavior. The description adds only a general privacy statement rather than any parameter-specific semantics, which is acceptable given the high schema coverage.

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', which provides a verb and object but leaves the classification scheme undefined. It does not distinguish this tool from the many sibling tools that also inspect URLs, refs, paths, or other inputs. The tool name 'compatibility' hints at the purpose but the description never explains what compatibility is being assessed against.

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 guidance about when to use this tool versus siblings like normalize-url, validate-json, or geo-hint. The privacy statement 'No identifiers are retained' suggests it is safe, but it does not state which inputs are expected, whether one field or many should be supplied, or what kind of request should be routed here.

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