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

With no annotations, the description carries the full burden. It states the output contains a list with specific fields, implying a read-only operation. However, it does not mention response format, pagination, or any potential requirements, leaving minor gaps for a simple list 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?

The description is a single, information-dense sentence with no fluff. It front-loads the verb and includes all essential details: scope, fields, and the purpose of the game= value.

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?

For a zero-parameter list tool with no output schema, the description is quite complete. It states the full set ('every game'), specifies the returned fields, and even explains the practical use. It could mention output format, but the description covers the key context for an agent to invoke it 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 tool has zero parameters, so the description is not required to explain any. The description focuses entirely on the output, which is appropriate and adds value by listing the exact fields returned.

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 uses the specific verb 'Lists' and clearly identifies the resource: 'every game supported by steamwebapi.com'. It further details the returned fields (slug, name, Steam appId, game= value), which distinguishes it from sibling tools like list_concepts and list_markets.

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 provides usage context by explaining that the tool returns 'the value to pass as `game=` in API queries', so an agent knows when to use it. It does not explicitly name alternatives or exclusions, but the purpose is clear enough to avoid confusion with sibling listing tools.

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