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

Beyond the annotations, the description discloses that no credit is consumed, the test game is capped at 3 players, it expires after 60 minutes, and it returns three types of links. It still leaves minor behavior unstated, such as whether repeated calls create multiple concurrent test games or how cleanup works.

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?

The description is three short sentences with no wasted wording. The mutation note is front-loaded, the usage context follows, and the return values are stated last, making it easy to scan.

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 single-parameter mutation tool with no output schema, the description supplies the important missing context: credit usage, player cap, expiry, intended use case, and return link types. An agent has enough information to decide whether and how to call it.

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 single quiz_id parameter is already fully documented by the schema. The description only reinforces that the quiz must be valid and adds no format or sourcing detail beyond what the schema provides; baseline 3 is appropriate.

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 states a specific verb and resource: start a test game of a valid quiz. It also clearly scopes the operation as a pre-event trial for the maker, which distinguishes it from siblings such as preview_quiz or create_quiz without needing to name them.

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 gives a clear usage context: 'Use it so the maker can try the quiz on their own phone before the event.' It does not explicitly state when not to use it or name alternatives like preview_quiz, but the intended scenario is unambiguous.

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