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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world behavior, so the safety profile is covered. The description adds material context beyond that: the explicit 5-credit cost and the fact that results are broken out overall and by format. It does not say what happens when the pair has never faced each other, but that is a minor omission for a read-only aggregate.

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 short clauses, front-loaded with the use case and metrics, then the cost. No filler and nothing redundant.

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, full annotations, and 80% parameter coverage, the description only needs to establish purpose and cost, which it does. The one gap is that it does not tell the agent that player ids must come from search_players, which matters for a tool requiring two ids.

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 80% and two parameters carry enums, so the schema already documents batter_id, bowler_id, league, and competition well. The phrase "overall and by format" hints that the format parameter is an optional slicing dimension, but no further detail is added beyond the schema baseline.

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 names the exact pairing (a batter against a bowler) and enumerates the returned metrics: balls, runs, strike rate, dots, fours, sixes, and every dismissal. That head-to-head framing is specific enough to separate it from broader siblings such as get_player_stats or get_deliveries.

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?

"Use for a batter against a bowler" gives a clear triggering condition, and the credit cost tells the agent about invocation expense. It stops short of stating when-not to use it (e.g., when only aggregate career stats are needed) or pointing at an alternative sibling.

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