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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered upstream. The description adds provenance of the data and the downstream id linkage, but says nothing about ordering, date range coverage, or how many events are returned for a no-parameter call.

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 no filler; the data source and the downstream id use both earn their place. Nothing is repeated from the title or annotations.

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 zero parameters and no output schema, the description needs to convey return content, which it does at a high level (event names/dates plus ids). It could be slightly more explicit about the shape of the returned record, but for a simple read-only list this is close to complete.

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 takes zero parameters, so there is no parameter meaning for the description to carry; baseline 4 applies. The description correctly implies the result set is fixed by Valve's calendar rather than filtered by caller input.

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?

Names a specific resource (Steam Next Fest and seasonal sale dates) and its provenance (Valve's published calendar), which tells an agent exactly what comes back. The verb is only implied via the name 'list', and it does not explicitly contrast with siblings beyond pointing at get_event_impact.

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 phrase 'with ids for get_event_impact' implies the natural follow-up call, which is useful workflow guidance. However, it never states when to call this versus other list-style siblings (e.g. list_games) or any prerequisites, so the guidance is implied rather than explicit.

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