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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds the underlying HTTP endpoint (GET /v1/customers/{id}), which is useful for mapping to the API but says nothing about error/not-found behavior or whether the call has side effects.

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 short sentences with no filler, and the resource-and-scope statement comes first. It is efficient, though it borders on under-specification rather than being genuinely concise.

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 one-parameter read-by-id tool with no output schema, the agent still lacks any hint of the returned customer shape or failure modes. The description is minimally adequate but does not close that gap.

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%: the single parameter is documented with pattern, length bounds, and a concrete 'cus_...' example. The description merely echoes the id format already in the schema, so 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 resource and scope: 'One customer by id (cus_...)' — singular retrieval, not a list. The 'one' vs the sibling shoprocket_list_customers is discernible, though the description never names the sibling explicitly.

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?

Usage is only implied by the name/verb: fetch a single customer when you have an id. There is no explicit statement of when to prefer this over shoprocket_list_customers or shoprocket_update_customer, and no note about what happens if the id does not exist.

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