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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds real context beyond that: Bookafy returns the entire list in one response rather than a truncated page, and next_offset can be fed back to continue reading — response-shape information that annotations do not carry.

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?

Three short sentences, front-loaded with what is returned before the paging guidance. The trailing 'GET /api/v3/customers' is mildly redundant for an agent but does no harm.

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 discloses the returned field set and the next_offset continuation token, which is exactly what an agent needs to page correctly. Missing only an explicit note on default ordering or volume limits, which are minor for a filtered list.

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%, with limit (1-500, default 100), offset (default 0, use next_offset) and search (case-insensitive name/email/phone) all documented in the schema. The description restates search's matching fields and the paging loop but adds no syntax or semantics the schema lacks.

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+resource ('List the account's customers') and enumerates the returned fields (id, name, email, phone, custom booking-form answers), which distinguishes it from write siblings like create_customer and update_customer. It does not explicitly name the sibling tools, but the read-only listing intent is unambiguous.

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?

Tells the agent to use `search` for name/email/phone matching and `limit`/`offset` to page, and communicates that the full list is returned at once so paging is a client-side concern. It stops short of stating when to prefer this over a direct customer lookup or which sibling to use for fetching a single customer.

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