get_hero_performance

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

Despite lacking annotations, the description explains what the tool returns (kills, deaths, assists, ability stats, per-fight breakdowns) and how time filtering affects results. It discloses that start_time/end_time filter fights, which is a behavioral trait not apparent from the schema. While it doesn't mention performance implications or auth requirements, the given details provide a reasonable understanding of the tool's behavior.

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 well-structured: a main summary, a list of return values, then parameter-specific usage notes and examples. It is appropriately sized for five parameters, front-loaded with the core purpose, and each sentence adds value without redundancy.

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?

Given the tool has an output schema (not shown) and this description covers all parameters, return content, and common usage scenarios, it is complete for the complexity involved. The combination of detailed parameter semantics and behavior descriptions leaves no major gaps for a user to start using the tool correctly.

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?

The schema has 0% description coverage, so the description must compensate. It does so thoroughly with an Args section that explains each parameter (match_id, hero, ability_filter, start_time, end_time), including examples for hero and ability_filter and time range semantics. This fully bridges the gap left by the sparse schema.

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 starts with 'Get comprehensive performance data for a hero' which clearly identifies the action, resource, and scope. It goes on to enumerate specific metrics (kills, deaths, assists, ability stats, per-fight breakdowns), which distinguishes it from sibling tools like get_hero_deaths or get_fight by showing it aggregates multiple performance dimensions.

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 provides explicit usage guidance for parameters: 'Use ability_filter for specific ability analysis' and 'Use start_time/end_time to analyze specific game phases' with concrete examples for common time ranges (early/mid/late game). It does not explicitly compare against sibling tools, but the context is clear enough to infer when this tool is appropriate.

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