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

Annotations already declare destructiveHint=true and readOnlyHint=false, and the description corroborates with 'Mutating'. It adds genuinely useful behavior beyond that: 'Only supplied properties change' (PATCH semantics) and 'null removes it' for the availability trigger. It does not state what happens to omitted nested collections like bulkDiscounts, which is the main remaining gap for a destructive write.

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?

Dense and front-loaded: the resource and scope come first, then the update semantics, then routing. 'and more' is the one wasted phrase, slightly undermining the enumeration it caps.

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 and annotations cover return shape and safety profile, so those needs are met. But for a 21-parameter mutation with 14% schema coverage, the description leaves most field semantics undocumented, which is a meaningful shortfall for correct invocation.

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 only 14% across 21 parameters, so the description must compensate and largely does not. It names a handful of fields and clarifies the trigger's null-removal behavior, but says nothing about layout, preselect, status, feeDisplay, the hideWhen* booleans, or what null means for the other nullable fields.

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 ('Update one ticket group on an event') and enumerates the modifiable surface: name, capacity, sale window, availability trigger, selection type, bulk discounts, visibility. An agent can distinguish this from update_ticket_type and update_event without opening any 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?

Routes the agent explicitly: ticket types belong to create_ticket_type/update_ticket_type/archive_ticket_type, and IDs come from get_event. That's clear context for when this tool is and isn't the right one, though it offers no explicit exclusion or precondition failure behavior.

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