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

Annotations already cover read-only, idempotent, non-destructive and closed-world, so the description does not need to restate safety. It adds genuinely new operational context: the 5-credit cost, which matters for tool selection under budget constraints. It does not describe caching or latency, but that is a minor gap.

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?

A single front-loaded sentence with the usage cue first, the returned fields second and the cost last. Every clause carries information; nothing is wasted.

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, annotations and fully described parameters, the description only needs to add the return-content summary and cost, which it does. A brief note on the credit cost being per call and on granularity versus get_pitches would close the remaining gap.

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%, so both parameters (pitcher_id, season with its default and game_id interaction) are already documented. The description only echoes season scoping at a high level and adds no syntax or format detail beyond the schema, which is the baseline case.

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 resource (a pitcher's arsenal for a season) and enumerates the returned metrics, so an agent knows this is an aggregated per-pitch-type breakdown rather than raw pitch data. It does not explicitly name the pitch-level sibling get_pitches, which would have made the distinction unmistakable.

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 pitcher's arsenal in a season" gives an implied usage cue and scoping condition, but there is no when-not guidance or named alternative (e.g. get_pitches for individual pitches). The agent must infer that this is the season-aggregate option.

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