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

Goes well beyond the annotations: it discloses that the retailer is notified, that a tracking link email is sent, the 72-hour fallback when the carrier is unsupported, the per-call confirmation default, that it reaches other people, and the required API key scope. This is rich operational context an agent could not derive from readOnlyHint/destructiveHint/openWorldHint.

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 and information-dense, but the parameter list is repeated nearly verbatim ('Add carrier, tracking number and package cost' then 'carrier, tracking number and package cost'), which is wasted text. Otherwise every sentence carries real behavioral 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?

For a write tool with no output schema, it covers the important agent-facing facts: side effects, notifications, fallback timing, confirmation policy, and auth. Minor gaps remain (no order-status prerequisite or error behavior), but nothing critical for correct invocation is missing.

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 description coverage is 100%, so the schema already documents all four parameters including the order_id format example. The description restates the same field list but adds no format, constraint, or edge-case detail beyond what the schema provides, so the baseline 3 applies.

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 (add) and resource (shipment) plus the exact fields involved (carrier, tracking number, package cost). It maps directly to a known portal action ('the same as Ship on your own'), so an agent instantly understands the operation and there is no sibling tool that could be confused with it.

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?

It conveys the situation (marking an order shipped with tracking) and notes the confirmation default, but never states when to use this versus alternatives such as faire_accept_order or other order updates, nor any prerequisite like order status. Usage is implied rather than explicitly scoped.

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