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

Annotations already cover readOnly, idempotent, closed-world and non-destructive, so the safety profile is settled. The description adds value beyond that by describing the shape of each returned entry and warning not to fabricate shipment_url values, but it says nothing about pagination or result-size limits.

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?

Front-loaded with purpose and contents, then usage examples, then sibling routing. Every sentence earns its place except the trailing shipment_url caveat, which is useful but slightly tangential to the tool's core job.

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?

With no output schema, the description correctly carries the burden of describing return entries (id, type, file name, processing status) and how to use shipment_url. An agent has everything needed to call and interpret this tool.

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% and the single parameter is fully documented in the schema with the same 'shp_123' example the description uses, so the description adds no meaning beyond it. Baseline 3 applies when the schema does the heavy lifting.

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+resource (list a shipment's documents) and enumerates the concrete contents (bill of lading, invoice, packing list, id, type, file name, status). It clearly differentiates itself from get_document_data and get_document_file, which are named directly.

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?

Gives explicit when-to-use examples ('which documents does shipment shp_123 have', 'is the certificate of origin missing') and routes the agent to the correct alternatives with conditions: get_document_data for content, get_document_file when `downloadable` is true.

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