find_rivals

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

With no annotations, the description carries full burden. It reveals behavioral traits: sorting by ELO-weighted net losses, a limit of 10 results, and return content (win/loss record, ELO context). It does not mention side effects or read-only nature, but these are implied for a query tool.

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 with no fluff: first sentence states the main purpose and sorting, second adds details about limit and output. Every sentence earns its place.

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?

Despite no output schema, the description fully explains return format (up to 10 rivals, win/loss, ELO context). Parameters are fully documented in schema. The tool is straightforward, and the description covers all needed context.

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% and the description does not add new meaning beyond the schema's parameter descriptions. It provides context about the output but not about the parameters themselves, so baseline score of 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?

The description clearly states the tool finds a player's rivals (opponents with a losing record) sorted by net losses weighted by ELO proximity, and explicitly mentions the purpose of identifying matchup weaknesses. This distinguishes it from sibling tools like get_versus or compare_players.

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 description implicitly indicates when to use this tool (when analyzing a player's weaknesses against multiple opponents) and provides details like returning up to 10 rivals. However, it does not explicitly state when not to use it or name alternative tools.

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