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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds only a pagination note (already in the schema) and the raw endpoint 'DailyMed v2: GET /uniis'; it discloses nothing about result ordering, total counts, or truncation behavior.

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?

Three short sentences, zero waste, with the core purpose front-loaded before supporting routing and endpoint detail. Nothing redundant or padded.

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 simple list tool with no output schema and fully documented params, the description covers what is returned (UNII codes and active-moiety names) and that results page. Only minor gaps remain, such as whether a total count or ordering is provided.

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%, with page and pagesize documented in the schema itself, so the baseline is 3. The description's '(paginated)' adds no syntax or default detail beyond what the schema already supplies.

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?

States a specific verb and resource ('List FDA UNII codes and their active-moiety names') plus the paginated scope. The mention of UNII codes/active moieties clearly separates it from siblings like dailymed_list_drug_names and dailymed_list_rxcuis.

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 tells the agent the downstream use of the output ('Use a unii_code to filter labels in dailymed_search_labels'), which implies when this tool is relevant. However, it never says when to choose this over the other list_* siblings (drug names, RxCUIs, drug classes) or any exclusion.

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