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

Annotations only declare read-only/idempotent/closed-world safety, but the description adds non-obvious behavior: selection is deterministic and no model generation occurs at request time, and nothing is persisted after the call. The note that the answer key is bundled changes how an agent should sequence its response to the user.

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 sentences, front-loaded with the resource and source, then usage, then exclusions — no filler. The opening sentence is long and packs the return payload into a dense clause, which slightly slows the read but every element is load-bearing.

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 four parameters and no output schema, the description still spells out the return shape (options, correct option, published explanation, stage citation URL) and discloses the determinism and no-persistence guarantees. Nothing an agent needs to call it and present results 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 coverage is 100%, so topic, language, difficulty and questionCount are already documented with ranges, defaults, enum values and fallback behavior. The description references `topic` and the stage-card source but adds no syntax or edge-case meaning beyond the schema, 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?

States a specific verb and resource ('Return a practice quiz') plus the exact content source ('original MasterAI Now knowledge-check questions selected from published stage cards'), and explicitly contrasts itself with search_content. An agent can distinguish it from get_content and search_content without opening any 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?

Gives a positive use case ('practice or checking understanding'), a presentation caveat (answer key included, so show questions first), and two explicit exclusions with an alternative named ('Do not use it to find lessons (use search_content)' and 'do not imply a score was recorded'). This is the full when/when-not/alternative pattern.

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