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

Annotations already cover the safe-read profile, and the description adds real context beyond them: no model is called, matching uses the same rules and stemming as site chat, and the interpretation is reported back in a read field. It also discloses the date-fallback ladder, though it does not describe result shape or limit behavior.

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?

Front-loaded with the core behavior and the sibling routing comes last, which is the right order. It is dense and slightly repetitive with three example sentences plus repeated language notes, but each sentence carries information an agent needs.

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?

A conversational, rule-based lookup tool with an output schema (including the read field the description references), full parameter documentation, and an explicit fallback policy. Everything needed to invoke it correctly is present.

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?

Schema coverage is 100%, so baseline is 3, but the description adds genuine meaning for previous — that missing topic, region, and date are inherited from the most recent prior question — beyond the schema's own wording. It also clarifies what the single question string may contain across languages.

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?

States a specific verb+resource: reads date, region, and keywords out of one sentence and finds events with it. It explicitly contrasts with search_events for the case where date and region are already known, so an agent can tell it apart from its siblings.

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?

Gives concrete when-to-use examples in four languages, says what happens when no date is present (today through weekend, then widening to 60 days), how to chain follow-up questions via previous, and names search_events as the alternative when date/region are known. Nothing is left to inference.

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