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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds real behavioral context beyond that: default page size (50), sort order (newest first), and the shape of what is returned. No auth or rate-limit details, but it goes meaningfully past the annotations.

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?

Purpose and behavior are front-loaded in a single dense sentence, followed by two short fragments. Every clause carries information; the only minor cost is that the field list is a long appositive run rather than being split out.

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?

There is no output schema, so the description correctly compensates by enumerating the returned fields. With 0 required params and full filter documentation in the schema, an agent has what it needs to call this correctly; only cross-tool routing guidance is thin.

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 88%, so the schema does most of the work, but the description adds two things not in the schema: the ANDed filter semantics and the default 50-per-page behavior (the schema's items_per_page states no default). This is above the baseline-3 case where the schema carries everything.

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 payments') and immediately enriches it with sort order (newest first), default page size, and the fields returned (product, price, discount, tax, coupon, affiliate, gateway, billing). This distinguishes it cleanly from the singular sibling learnworlds_get_payment.

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?

Provides a composition rule ('All filters are ANDed') which is genuine usage guidance for combining the 8 optional filters. However, it never names when to use this versus learnworlds_get_payment, nor any exclusions or prerequisites, so routing relies on inference from the list/get naming.

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