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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description usefully discloses the returned fields (id, title, colour), but it says nothing about pagination behavior or whether the full label set is returned, which matters given page and page_size parameters.

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?

Two short sentences with zero waste. The resource and returned fields come first, and the actionable next step (use the id with semble_add_patient_label) follows.

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 small read-only list tool with no output schema, the description compensates by naming the returned fields and the key identifier to use downstream. The only material gap is pagination semantics, which the schema partially covers.

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 page, search, and page_size are fully documented in the schema. The description adds no additional meaning about how searching or paging interacts with the returned labels, leaving it at the baseline.

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 names the specific resource ('labels that can be put on patients') and the fields returned (id, title, colour), which makes it distinguishable from siblings like semble_add_patient_label. The verb 'list' is only implied via the title rather than stated explicitly, keeping it just shy 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?

It gives a clear downstream use case ('Use the id with semble_add_patient_label'), which implies when to call it — before adding a label. However, it does not say when not to use it, does not mention the search parameter as a way to find a specific label, and does not address alternatives.

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