beel_list_customers

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

Annotations already carry the safety profile (readOnlyHint=true, idempotentHint=true, openWorldHint=true, destructiveHint=false), so the bar is lower. The description adds genuine context beyond annotations by stating the endpoint, the pagination behavior, and the fact that only the path company's customers are returned. It does not contradict annotations — 'Returns a paginated list' aligns with the read-only hints — but it doesn't elaborate on error or edge cases, so a 3 is fair.

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 with no fluff, front-loaded with the core purpose. The scope restriction is placed early. The endpoint line is marginally redundant since the path is implied by the company_id parameter, but it's still efficient documentation reference. Nearly zero waste.

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 filtered list tool with 100% schema coverage and a rich parameter set, the description covers the essentials: pagination, filtering, and scope restriction. The default active=true behavior is already in the schema, so not repeating it is fine. With no output schema present, a brief note on return shape could help, but the definition is adequate for an agent to call it correctly.

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 the schema already documents all 13 parameters in detail (e.g., active defaulting to true, deleted customers never returned, NIF reachability behavior). The description only adds 'with optional filters', which adds little over the schema. Baseline 3 is appropriate since the description doesn't need to compensate for a coverage gap.

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?

The description states a specific verb-object pair ('Returns a paginated list of the customers of this company (NIF)') with optional filters, making the resource and scope unambiguous. It clearly differentiates from siblings like beel_list_invoices and beel_list_products by naming customers specifically, and the title 'List Company Customers' reinforces it. An agent can tell what it does without opening the schema.

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 description notes the scope restriction ('Only the customers of the company in the path are returned') and mentions optional filters, giving useful context for when pagination/filtering is needed. However, it never explicitly names alternatives (e.g., beel_get_customer for a single customer, beel_create_customer for adding) or states when-not conditions. The guidance is implicit context, not active routing.

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