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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful behavioral context beyond that: the data source (XP marketplace catalog), the returned fields, and a caching instruction to avoid re-calling for the same event_id.

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 sentences, front-loaded with the trigger and payoff, then the exclusion. Every clause carries either usage routing, return contents, or a caching constraint — 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?

An output schema exists, so the description needn't document return structure, and it nonetheless summarizes the card's contents. For a single-parameter read tool, routing, behavior, and caching guidance are all 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 description coverage is 100%, so the lone `event_id` parameter is already fully documented in the schema, including its provenance from search_events. The description adds no syntax or format detail beyond what the schema provides, so the baseline of 3 applies.

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 and resource — returning the 'full event card' with named contents (venue, performers, fee-inclusive price preview, images) — and explicitly contrasts itself with `get_ticket_listings`. An agent can distinguish it from the many sibling search/get tools without opening a 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?

It gives a concrete trigger ('event ID is in hand and the user wants the full event card before browsing tickets') and an explicit exclusion ('Do not use to list ticket inventory; `get_ticket_listings` is the right tool'). Both when-to-use and when-not-to-use are named with the alternative.

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