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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds context about the 'web' availability and return fields, but discloses no additional behavioral traits such as auth needs, rate limits, or pagination, which are not critical here. The description does not contradict 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?

Two sentences with zero wasted words: the first states the resource and return contents, the second gives the usage trigger. The most important information is front-loaded.

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 simple read-only listing tool with one optional, well-documented parameter and no output schema, the description is complete: it lists the return fields, states the usage context, and annotations cover side-effect safety. Nothing an agent needs to call it correctly is missing.

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%, and the single optional 'period' parameter already has an enum and a clear description ('Return only the plans billed with this period'). The tool description adds no extra meaning about the parameter, 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?

The description uses a specific verb ('Returns') tied to a concrete resource ('SuperȘcoala subscription plans available on the web') and enumerates the exact data fields returned. It clearly distinguishes this pricing/subscription tool from the educational-content siblings like list_subjects, list_teachers, and get_lesson.

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?

It explicitly states when to use the tool: 'Use it when someone asks what access costs or what a plan covers.' It does not explicitly name alternatives or exclusions, but none of the sibling tools overlap in purpose, so the context is clear enough.

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