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

readOnlyHint=true already establishes this is a safe read, so the description's main added value is that search is a contains match across name and email and results are paged. It says nothing about result ordering or return shape, and it silently omits the sort capability that the tool actually offers.

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?

A single tight sentence with the core purpose front-loaded and the qualifiers (search, paging, endpoint) trailing. Nothing is padded or redundant.

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 list tool with no output schema, the agent still lacks basics such as whether a total count or cursor is returned, the default ordering, and the presence of sorting. The endpoint hint is useful but does not substitute for that missing operational context.

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 80%, so the baseline is 3. The description adds real meaning for `search` (which fields it matches, contains semantics) beyond the bare 'Text to search for', but sort_by and sort_direction go unmentioned, leaving those to the bare enum.

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 ('List customers') plus the two notable capabilities, search and paging, so an agent knows exactly what operation this performs. It is distinguishable from the get_customer sibling by the plural/list framing, though it never names that 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: 'optional text search over name and email' hints that this is for browsing or finding customers, but there is no statement of when to prefer this over twicecommerce_get_customer (single lookup) or how to page through large result sets. No exclusions or alternatives are given.

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