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

The readOnlyHint annotation already declares this a safe read operation, so the description's main added value is disclosing the returned field set and the expand option. It says nothing about auth scopes, rate limits, or behavior with a nonexistent event_id, which would be the sort of extra context that raises this above baseline.

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?

Three short, front-loaded sentences with no filler: purpose and return fields first, the expand hint second, the underlying endpoint last. Every sentence earns its place.

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?

With no output schema, the description usefully enumerates the shape of the response, compensating for that gap. Only minor omissions remain (pagination is irrelevant for a single fetch, and error behavior is unstated), so it is nearly complete for a 2-parameter read tool.

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 there, so the schema carries the load. The description's expand example ('venue,ticket_classes') roughly duplicates the example already in the schema description, adding little new meaning; baseline 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 and resource ('Fetch one event') and enumerates the returned fields (name, summary, start/end, status, capacity, venue_id, listing settings), which separates it from list_events. It does not explicitly name the nearest siblings (e.g. get_event_description, get_capacity) that return overlapping data, so the differentiation is only implicit.

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 only guidance is 'Use expand=venue,ticket_classes for more', which tells the agent how to get richer output but not when this tool is preferable to list_events, get_event_description, or get_capacity. No exclusions or prerequisites are given, so usage is only implied.

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