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

With annotations present, the bar is lower, but the description still adds significant value: it discloses that data is refreshed from Ticketmaster when stored data is older than 6 hours, and that the tool returns source records and a change history. This consumer-facing behavioral context goes beyond the generic idempotentHint=false and openWorldHint=true annotations. It does not, however, explain rate limits, auth needs, or why idempotentHint is false for a 'get' operation.

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?

It is a single, front-loaded sentence that packs purpose, return fields, and a behavioral note (6-hour refresh) without wasted words. It is dense and readable. Slightly longer than strictly necessary, but every clause carries information.

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 one-parameter lookup tool with no output schema, this description is nearly complete: it tells the agent what the tool returns, how to obtain the event_id, and when stored data is refreshed. It lacks explicit guidance on error cases (invalid event_id) and does not resolve the annotation tension regarding readOnly/idempotency, but it covers the essential call mechanics.

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 description coverage is 0%, so the description must compensate. It does explain what the single parameter is – an event_id obtainable 'from any other tool' – which is useful routing context. But it does not add format, length, or validity details beyond the schema's minLength: 1 and maxLength: 120. Baseline 3 is appropriate for a single-param tool with material description coverage but no syntax detail.

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 states a specific verb+resource ('Full details for one event by event_id') and distinguishes itself from siblings with the parenthetical '(from any other tool)'. It also enumerates exactly what details are returned, making the purpose unambiguous without opening the 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 makes clear this is the lookup tool you call with an event_id obtained from any other sibling, providing context on when to use it. However, it does not name an explicit alternative or state exclusions (e.g., 'if you have no event_id, use search_local_events first'), so it stops short of a 5.

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