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

Annotations declare readOnlyHint=true and openWorldHint=true, so safety profile is known. The description adds valuable context: it works with English or Chinese product descriptions, accepts either product or commodity code, and flags China-specific anti-dumping/countervailing duty - behavior beyond the annotations. It doesn't mention output format or limitations, but with annotations covering safety, this is strong.

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 sentences, front-loaded with the usage condition, then the action and special flag. No waste, every clause earns its place.

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 read-only lookup tool with full schema and annotations, the description covers when to use, what it returns (commodity code and duty rate), and a special behavior (anti-dumping flag). It doesn't describe output format, but no output schema exists, so a small gap remains; still, an agent can invoke it correctly.

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 coverage is 100%, so all three parameters are already well-documented. The description adds that product can be English or Chinese and that either product or commodity code can be used, but this is largely redundant with the schema. Baseline 3 is appropriate.

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 (finds commodity code and duty rate) and resource (UK duty rate), plus scope (imports from China to UK). Clearly distinguishes from siblings like check_anti_dumping and find_uk_compliance by focusing on duty rate lookup.

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?

Explicitly says 'Use when the user asks what duty rate or commodity code applies to a product imported from China to the UK' and clarifies it accepts either product description or commodity code. It also mentions flagging anti-dumping duty, which hints at its relationship to check_anti_dumping without confusing the primary purpose.

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