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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so safety is covered; the description goes beyond them by disclosing the response envelope { results, count, has_more, next_cursor } and the underlying GET /v1/customers endpoint, plus the cursor-based pagination contract. It does not mention rate limits or ordering of results.

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 tight sentences: the first front-loads the filter capabilities, the second gives the return shape and endpoint. Nothing is redundant and no sentence is 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?

With no output schema, the description usefully supplies the return keys and paging fields, and the cursor parameter's meaning is anchored to next_cursor. Only minor details (result ordering semantics, behavior when multiple filters combine) are left unstated.

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 all ten parameters are already documented — baseline 3. The description's only marginal additions are restating the filter groupings and the location+radius coupling (including miles), which the schema itself already spells out for radius.

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/search customers) and enumerates the actual search modes — name/email/phone, creation time, and geographic proximity — which clearly separates it from get_customer and create_customer among its siblings.

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 search modes imply when this tool is appropriate, but there is no explicit routing guidance such as 'use get_customer when you already have an ID' or any condition under which this tool should not be used. Usage is inferable but never stated.

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