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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds genuine context: the exact REST path and the shape of each returned list entry. It stops short of discussing pagination behavior or the permission/scope needed to see lists.

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, zero waste: the resource and its returned fields come first, followed by the actionable 'what to do with the id' guidance. The parenthetical field list is dense but informative.

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 carries the burden of describing return values and does so at a useful level (id, name, products, date, rules); pagination is delegated to the fully described page/page_size schema. Minor gap: no note on empty results or the ordering of lists.

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%, so every parameter (event, organizer, subevent, page, page_size) is already documented in the schema, including the organizer single-token nuance. The description only echoes 'event' and 'event series date' without adding format or filtering semantics beyond the schema, so baseline 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?

States a specific verb and resource ('List the check-in lists of an event') and enumerates the salient returned fields (id, name, admitted products, series date, rule settings), which distinguishes it from siblings like pretix_get_checkin_list_status and pretix_list_checkin_list_positions.

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?

Explicitly routes the agent forward: 'Use the list id for check-in status, attendee lists and check-in,' which clarifies this is the discovery step preceding those tools. It does not name an alternative tool or state when not to use it, keeping it 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.