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

Annotations already indicate the operation is a non-read-only, non-idempotent write that is not destructive. The description adds the target entity and the dependency on smi_add_subject_employee, but it does not disclose additional behavioral traits such as duplicate handling or whether multiple URLs can be attached. No contradiction with annotations.

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?

A single sentence front-loads the action and target, then specifies the ID source. There is no filler or repetition.

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 two-parameter tool with complete schema coverage and an output schema, the description supplies the essential relationship to smi_add_subject_employee and enough context to invoke it correctly. It loses a point only because it leaves the distinction from sibling URL tools implicit.

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 both parameters already have meaningful descriptions. The description's mention of subjectEmployeeId being returned from smi_add_subject_employee essentially repeats the schema's parameter description, adding no new semantic information.

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 uses a specific verb ('Attaches') and names the exact resource, an SMI subject employee, and the ID it operates on. It is clear but does not explicitly differentiate itself from sibling tools like smi_add_subject_url or smi_add_subject_relationship_url, so it stops short of a 5.

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?

The description gives clear context by stating the URL is attached to a subject employee using the subjectEmployeeId returned by smi_add_subject_employee, implying a sequencing dependency. However, it does not explain when to choose this tool over the sibling URL-add tools, so it lacks explicit exclusions.

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