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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered; the description adds only the return field set. It says nothing about pagination behavior, empty-result handling, or result ordering, which are the behaviors an agent would still need to reason about.

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 compact fragments with zero filler and the key resource stated first. Slightly telegraphic but nothing wasted.

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 read-only per-customer list with a fully documented schema and no output schema, the description covers purpose and returned fields adequately. A brief note on pagination iteration would close the remaining gap, but the schema already documents it.

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 parameter descriptions already explain offset, page_size ranges and the next_offset chaining. The description adds no parameter meaning beyond the schema — 'one customer' merely restates that customer_id is required.

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?

Names a specific resource ('contact people of one customer') and enumerates the returned fields (name, email, phone, title), plus the underlying endpoint. It is distinguishable from siblings like get_customer or list_customer_ship_to_locations, though the verb 'list' comes only from the title rather than the description body.

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 scope ('of one customer') implies you need a customer id and that this is per-customer lookup, but there is no explicit when-to-use versus get_customer or list_customer_ship_to_locations, and no stated precondition or exclusion. Usage must be inferred.

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