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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful context beyond that: price/availability are source-reported (possibly stale), the source should be rechecked before purchasing, and no booking occurs. It doesn't cover error behavior for stale ids, keeping it short of a 5.

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?

Two tightly written sentences with the lookup action front-loaded, followed by what is returned and the critical purchasing caveat. No filler.

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?

Despite no output schema, the description enumerates what is returned (date, place, price/availability, links), covers the id provenance, and flags the non-transactional nature of the tool. Nothing essential for correct invocation is missing.

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% and both parameters are documented, including the 64-character id pattern and the sandbox flag. The description's mention of the 'full id from search_events' largely restates what the schema already says, so the baseline of 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?

States a specific verb (look up) and resource (upcoming public event) plus the exact identifier needed. It also names the sibling tool search_events as the source of the id, so an agent can distinguish it from the search tool without opening either schema.

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 tells the agent when this tool applies (after obtaining an id from search_events) and draws a clear boundary: 'this tool does not book or buy tickets.' It does not give an explicit when-not scenario beyond that, but the sequencing guidance is clear.

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