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

Annotations already declare readOnlyHint=true and a 'List or search clients' title, so safety is covered. The description adds useful behavioral context with 'Paged', but discloses nothing about result limits, ordering defaults, or what the response contains.

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, front-loaded with the operation and resource, then the filter dimensions, then the paging note. No redundant or filler text.

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 12-parameter read-only list tool with no required params and full schema coverage, the description covers purpose, filters, and pagination. It leaves return-shape and result-cap details unstated, but the absence of an output schema makes this a minor gap.

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 every parameter (name, note, page, tags, email, order_by, first/last_name, invoice_id, country_code, client_number, per_page) is already documented in the schema. The description only summarizes these filters and adds no format or syntax detail beyond it, so 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 ('List') and resource ('clients/customers') and enumerates the filterable dimensions, so the agent knows it is a filtered-listing tool. Sibling differentiation (vs billomat_get_client or billomat_create_client) is implied by 'List' rather than stated 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?

The filter list implies the search/retrieval context, but there is no explicit when-to-use guidance, no mention of when to prefer billomat_get_client (single client) over this list, and no stated prerequisites. Usage is inferable rather than directed.

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