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

Beyond the annotations, it explains the puzzling detail that this is read-only despite being a POST (request body), which prevents an agent from mistaking it for a mutation, and it discloses the per-product result fields (fixed amount, percentage, total cost, reductions). It does not cover rate limits or auth requirements, so not a 5.

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 compact sentences: the capability and return shape come first, the read-only/POST clarification second. Nothing is redundant and nothing needs re-reading.

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 carries the burden of describing results and does so (fixed amount, percentage, total cost, reductions). Only auth/permission or rate-limit context is missing, which is minor for a read-only calculation.

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%, so the baseline is 3, and the description adds value by mapping the composite input to meaning: one entry per EAN, selling price required, condition optional, batch capped at 100. It also implicitly ties each input record to the breakdown returned, which the schema alone does not convey.

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 (calculate bol's commission) plus scope (up to 100 products, per EAN with price and optional condition) and even names the underlying endpoint. No sibling tool competes for this purpose, so an agent can select it unambiguously.

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?

Usage is implied by the purpose statement (batch commission lookup) but there are no explicit when/when-not rules or named alternatives. The sibling list contains no overlapping commission tool, so the risk of misrouting is low, but the description does not actively help the agent decide.

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