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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral details beyond this: it reports the highest documented tier, handles the case of no criteria on file, and clarifies the tool's advisory role. This enriches the agent's understanding of edge cases and boundaries without contradicting 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?

The description is a single paragraph of five sentences, each sentence earning its place: usage trigger, return value, tier matching logic, edge cases, and a disclaimer. It is front-loaded with the trigger condition and remains focused without unnecessary detail. This is appropriately concise and well-structured.

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?

Despite lacking an output schema, the description thoroughly explains all return scenarios: the matching tier, next tier, higher tiers, highest tier already reached, no criteria on file, and the advisory disclaimer. This provides a complete picture of the tool's behavior for an agent, covering complexity without leaving significant gaps.

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?

The input schema has 100% description coverage for both parameters ('conditionName' and 'currentPercent'), so the baseline is 3. The description does provide context by explaining how the parameters fit into the tier comparison process, but it does not add significant new semantics beyond what the schema already conveys. It neither harms nor greatly enhances parameter understanding.

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 clearly states what the tool does: compares a condition and current percentage against VASRD criteria and returns tier information. The phrase 'Use this when a veteran gives a condition name and the percentage...' provides a specific verb-resource-scope structure. It differentiates itself from potential siblings by focusing on the analysis of a rating gap, though it does not explicitly mention sibling tools.

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 explicit when-to-use guidance ('Use this when a veteran gives a condition name and the percentage...') and includes a useful caveat about VA authority. However, it does not mention alternatives or when not to use the tool, such as comparing to the sibling 'compare_rating_criteria'. Since it provides clear usage context but lacks exclusions or alternative tool mentions, it falls short of a 5.

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