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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds that results are ids and names and that the method name feeds order placement, but says nothing about rate limits, transient data, or what happens with unsupported country codes — the open-world risk the annotation flags.

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?

Three short sentences with the resource and return shape front-loaded and the downstream requirement placed last where it belongs. The trailing 'GET /shipping' is mild filler but not harmful.

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?

There is no output schema, so the description carrying 'ids and names' is valuable, but it is only a partial account of the response for an open-world list tool. Nothing an agent needs is dangerously missing, but the definition is thin for a tool with no structured return documentation.

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 country_code pattern and the US default are already fully documented in the schema. The description only says 'for a destination country' and adds no syntax, format, or default detail beyond that.

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 and resource ('shipping methods CustomCat offers') and scopes it to a destination country, plus notes the return shape (ids and names). It does not explicitly distinguish itself from the sibling customcat_get_shipping_cost, so it falls short of a 5.

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 line 'The method name is required when placing an order' implies the tool is a prerequisite lookup for customcat_create_order, which is useful implied usage. However, there is no explicit guidance on when to use this vs customcat_get_shipping_cost, and no stated alternatives or exclusions.

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