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

With no annotations, the description carries the full burden. It discloses that results are current, that each rule includes its source record and date, and that it includes struck-down, expired, and superseded items. This is substantial behavioral context, though it does not describe the exact return shape or formatting.

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 dense but purposeful sentences. The first front-loads the tool's content and provenance format; the second delivers an actionable usage warning. No filler or redundant phrasing.

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 optional-parameter lookup with no output schema, the description gives enough context to invoke correctly and interpret results. It could be slightly more complete by explicitly mapping the part enum to the listed components, but the schema already covers that.

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 schema covers the single optional `part` parameter with clear enum values and a description, so baseline is 3. The tool description does not discuss `part` directly, but the enumerated content helps contextualize the 'superseded' and 'fees' parts without adding new parameter-level semantics.

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 defines the resource: a China→US import duty stack returned rule by rule, with establishing record and date. It enumerates the exact rules and fees included, making its scope unmistakable and distinguishing it from more focused sibling tools like section_301_ladder or import_rule_changes.

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 guidance: 'Use this before quoting any US import rule from memory,' with a strong rationale that 2025 training guidance is superseded. It does not name alternative tools or state when not to use it, but the context is clear enough for an agent to know when this lookup is appropriate.

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