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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds valuable behavior beyond those annotations: exact return fields, ordering, locale behavior ('in any of the 13 site languages'), the fallback to English, and the exclusion of betting editorial.

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?

Three dense sentences with no filler: the first defines scope and behavior, the second states the return contract and follow-up action, and the third states the exclusion. Key facts are front-loaded and every sentence 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?

The description is nearly complete: it covers purpose, ordering, languages, returned fields, and the next step to get_article, and the schema fully documents all parameters. A minor gap is that neither q nor tag is marked required, and the description does not state what happens if both are omitted.

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 input schema has 100% description coverage across all five parameters, so the schema already documents each parameter. The description reinforces q and tag ('by keyword or tag') and locale ('13 site languages'), but it adds little new semantic detail beyond what the schema provides; baseline 3 is appropriate.

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 opens with a specific verb and resource: 'Search UFCalendar's own editorial archive', then enumerates content types, sorting ('newest first'), and language scope. It also differentiates itself from siblings by stating that it returns metadata only and that 'Betting editorial is not served.'

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 gives clear context for when to use the tool — searching UFCalendar's editorial archive by keyword or tag — and explicitly routes users to get_article for the body. It also states an exclusion (no betting editorial), but it does not enumerate when alternatives like search, search_fighters, or search_venues should be preferred.

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