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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so safety is covered. The description adds genuine beyond-annotation value: pagination behavior (up to 100 per page, pass next_cursor as cursor) and the auth requirement (Cotlet API key with app access).

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?

Front-loads the resource and returned fields, then covers filtering, pagination, and auth. Minor redundancy between 'Clients in your catalog' and 'Lists the clients saved in the account catalog', but overall tight and well-ordered.

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 list tool with no output schema, the description covers returned fields, filtering, pagination, and auth, and cross-references the downstream create_invoice use. An agent has everything needed to call it and page through results.

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 three parameters are already documented. The description restates the search semantics ('name or RFC') and the cursor flow, but adds no syntax or format detail beyond the schema, so the 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), enumerates the fields returned (RFC, name, CFDI use, tax zip code, fiscal regime), and scopes it to the account catalog. This clearly distinguishes it from siblings like get_client, create_client, and list_invoices.

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?

Gives clear context (filter by search text on name or RFC, use client_id in create_invoice) and pagination instructions, but never explicitly contrasts with get_client for single-record lookups or states when-not to use this tool.

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