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

With no annotations provided, the description carries the full burden. It discloses that the tool returns counts by letter (A-Z, 0-9, other), which gives some transparency about the output. However, it omits important details such as whether zero-count letters are included, what 'other' precisely covers, and the exact response format. This is a moderate disclosure.

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 a single efficient sentence that front-loads the core functionality and then adds the use case. There is no redundant or filler wording; every word contributes to understanding the tool.

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 absence of an output schema and annotations, the description must explain more about the return value and edge cases. It only says 'per-letter game count' without specifying the structure of the result, what happens for systems with no games, or how 'other' is defined. This is insufficient for a tool with no structured documentation to rely on.

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 description coverage is 0%, and the description only says 'for a system' without explaining what a system is, whether it's an ID or name, or any valid values. The tool name already implies the per-system scope, so the description adds minimal semantic value. The parameter meaning is largely left to the agent's inference.

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 what the tool does: it returns per-letter game counts for a given system, including numbers and 'other'. This is a specific verb+resource+scope that distinguishes it from sibling tools like get_game (individual game details) and list_systems (system list). The alphabet navigation use case further clarifies its purpose.

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 a clear use case ('useful for alphabet navigation'), which tells the agent when to use it. However, it does not explicitly mention alternatives or when not to use it, so it falls short of a 5 but earns a 4 for clear context.

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