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

Annotations declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so safety is covered structurally. The description adds valuable context beyond annotations: it is a small free sample, not the full bank, questions are independent study checks rather than official exam questions, and clients supporting MCP Apps render it as an interactive quiz card. It doesn't mention rate limits or pagination behavior.

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, front-loaded with the return shape and immediately followed by usage guidance and scope limits. Every clause earns its place without repetition.

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?

Given an output schema exists, the description need not explain return values, yet it still summarizes the item shape. Combined with annotations for safety, documented params, and explicit scope boundaries, an agent has everything needed 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 baseline is 3. The description reinforces the country parameter ('for one country') and the sample nature implies a small count, adding minor semantic context beyond the schema which already documents count limits and country examples.

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 ('Returns free multiple-choice practice questions for one country') and enumerates the exact shape of each item: four options, zero-based answerIndex, and explanation. This distinguishes it clearly from siblings like get_official_sources or get_track_info.

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 a clear trigger condition ('when the user wants to practise, be quizzed or see example questions') and contrasts the tool's scope with the full bank and official questions. It lacks explicit 'when not to use' guidance for the sibling tools, but the usage context is unambiguous.

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