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

Annotations are only readOnlyHint=false/destructiveHint=false, so the description carries the real burden and does so well: it discloses that enter registers an explicitly selected brokerage account, that rulesAccepted must follow user acceptance, that eligibility checks saved entry requirements, and that withdraw removes an entry only while registration rules permit. Slight tension: withdraw deletes an entry while destructiveHint is false, which is defensible for a registration but worth flagging to the agent; no rate limits or response shape beyond annotations are given.

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?

Front-loaded with the resource and a compact action map, and nearly every sentence carries a distinct constraint. It is dense with seven actions compressed into one paragraph, and the trailing 'Use contest and account names in your reply' is response guidance rather than tool semantics, so it is not perfectly lean.

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 no output schema, the description does well to say results include rules, prizes and account leaderboards. Prerequisites (explicit broker credential, accepted rules, qualifying purchases for eligibility) and the no-charge/no-trade boundary make it callable without guesswork; minor gaps remain on what 'eligible' returns and any pagination.

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 80% and the description adds meaning on top: brokerCredentialId is an 'explicitly selected brokerage account' (user choice, not bot-chosen), rulesAccepted is gated on user acceptance, and botId is a legacy identity only for withdraw. contestId scope is left to the schema's 'required for every action except list.'

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 the resource (public trading competitions, rules, prizes, leaderboards) and then maps each of the seven action values to a distinct verb ('list finds competitions; get reads one; leaderboard follows entered accounts; my_entry reads your own entry'). It also explicitly rules out sibling territory by noting it does not place trades or start a bot, so an agent can separate it from place_trade/start_deployment.

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?

Every action gets a when-to-use sentence, including sequencing constraints ('Read the rules with get and set rulesAccepted=true only after the user accepts them') and the eligibility precondition check. Alternatives and exclusions are named: 'no strategy or bot is required' and 'does not place trades, start a trading bot or charge money.'

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