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

No annotations are provided, so the description carries the full burden. It discloses important limitations: owner codes are not resolved to a company, and a valid number is self-consistent but not proof the box exists. It also explains the meaning of the category letter (U, J, Z, R). This adds valuable behavioral context beyond the schema.

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 concise and well-structured. It opens with a clear one-sentence definition, then provides context, limitations, and category meanings in efficient sentences. There is no wasted wording; every sentence adds value.

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?

Given the tool's complexity (single parameter, no output schema), the description is quite complete. It explains the standard, common相交s,the李晓明提供背景, limitations, and usage context. It could arguably cover failure scenarios, but for a simple validation tool it is strong.

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% (the single parameter 'code' is fully described in the schema), so baseline is 3. The description adds value by providing an example ('CSQU3054383') and clarifying the structure (owner code, category letter, serial, check digit), which gives semantic meaning beyond the schema's generic description.

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 explicitly states the tool 'Validates an ISO 6346 freight-container number' and enumerates the components (owner code, category letter, serial, check digit), which is a specific verb+resource. It distinguishes itself from siblings by focusing on container validation, unlike bic_validate or shipping_identify.

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 explains when to use it: 'Bills of lading and terminal scans mistype container numbers constantly; the check digit catches almost all of those before a customs filing.' It implies use for validating container numbers in shipping contexts, but does not explicitly contrast with siblings like shipping_identify, though the context is clear.

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