Ranked retrospective race turning-point candidates.

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

Annotations already declare read-only, idempotent, non-destructive, open-world behavior, so the safety profile needs no restating. The description adds genuinely non-obvious context: results are computed with future race information and ranked by a fixed heuristic, which tells the agent the output is hindsight-derived and deterministic rather than model-predicted.

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 short sentences, front-loaded with the core purpose, then method, then caveat. The opening sentence largely restates the title, which is the only wasted wording.

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 an output schema present, the description need not explain return values, and all three parameters are fully documented in the schema. What remains for the description — purpose, ranking method, and the retrospective caveat — is covered, and a read-only tool needs no further precondition detail.

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%, with year, round, and limit all documented including defaults and ranges, so the schema carries the parameter burden. The description adds no extra meaning about parameter interaction (e.g., whether limit truncates the ranked list), 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: it ranks observed race events into retrospective turning-point candidates. The clarification that ranking follows a 'fixed event-kind heuristic' and is 'not a live forecast or win-value model' separates it from predictive siblings such as f1_retirement_risk, though no sibling is named directly.

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?

The word 'retrospective' plus 'not a live forecast' gives a clear condition for use (post-race analysis) and an explicit exclusion (live/in-race decision making). It stops short of naming a concrete alternative tool to use instead, which would have pushed this higher.

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