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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds only the REST path (GET /api/customer/{uuid}.json), and stays silent on auth requirements, error/not-found behavior, and what fields come back.

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 the action and the lookup key front-loaded; nothing is padded. The raw endpoint string is mildly redundant for an agent but not wasteful.

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 tool with rich annotations, the description covers the essentials of selection and invocation. With no output schema, though, it should at least sketch the returned contact payload or note that a missing UUID yields an error, which it does not.

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?

There is a single parameter and schema description coverage is 100%, with the UUID format pattern documented in the schema itself. The description only restates that the lookup key is a UUID, adding no syntax or semantic detail beyond the schema, 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 and resource ('Retrieve one contact (customer)') plus the lookup key ('by UUID'), which implicitly separates it from list_customers and get_customer_by_phone. It stops short of naming those siblings explicitly, so an agent must infer that UUID-keyed retrieval is the unique scope of this tool.

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 phrase 'by UUID' implies the precondition for using this tool, and the sibling get_customer_by_phone makes the alternative obvious by contrast. However, no explicit when-to-use, when-not-to-use, or fallback guidance (e.g. 'if you only have a phone number use get_customer_by_phone') is given.

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