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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real context beyond that: the returned set is limited to current and recent weekly/premier events, and the output is meant to be consumed as an auction_urn by another tool. No contradiction with annotations.

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 sentence with no filler. The resource scope is front-loaded and the cross-tool dependency is a tight trailing clause; every element earns its place.

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, read-only discovery endpoint with an output schema and clear annotations, the description supplies everything an agent needs: what data comes back, how fresh it is, and how the result is consumed downstream.

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 are no parameter semantics to explain and the baseline is 4. The description correctly implies a discover-and-enumerate call rather than a filtered query.

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 (weekly and premier auction events on Fanatics Collect) and bounds it temporally to current and recent ones. It also positions itself against the sibling fanaticscollect_search by declaring itself the discovery endpoint feeding that tool's auction_urn param, so an agent can tell the two apart without reading schemas.

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 'the discovery endpoint for fanaticscollect_search's auction_urn param' tells the agent exactly when to reach for this tool: to resolve a valid auction_urn before calling search. It gives no explicit when-not guidance, but the use case is unambiguous.

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