List a city’s events for a day

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

Annotations already provide readOnlyHint, openWorldHint, idempotentHint; description adds 'Read-only' and clarifies default behavior (date defaults to today) and invalidity of national hub, exceeding the hints.

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?

Concise: two main sentences with no redundancy; front-loaded with purpose, then parameter details and sibling references. Every sentence adds 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?

Fully describes the tool's output (time, price, venue), references for full details (otc_get_post), and covers all parameters with no gaps. Completeness is high despite no output schema.

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 covers 100% of parameters with descriptions, but description adds crucial context: site aliases, invalid site, date format, and free_only filter behavior, significantly enhancing parameter understanding.

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?

Clearly states the verb 'List' and specific resource 'events from an on the Cheap city calendar', and distinguishes from siblings like otc_search_posts and otc_get_post by mentioning alternative uses.

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?

Explicitly states when to use (for a given date), what not to do (national hub is invalid), and references sibling tools for related tasks (otc_list_sites, otc_get_post).

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