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

Annotations already declare readOnlyHint=true and destructiveHint=false, so safety is covered. The description adds that the figures are 'live' (a point-in-time snapshot rather than historical totals) and outlines the response breakdown, but says nothing about freshness/latency, whether cancelled orders are excluded, or how 'inside now' differs from 'checked in'.

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 tight sentences; the payload description is front-loaded and the return content is enumerated compactly. The trailing raw endpoint path is slightly redundant for an agent but does no real harm.

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?

Reasonable for a read-only metrics endpoint with no output schema, since the description sketches the return shape. It still leaves ambiguity about semantics of the counters (e.g. does 'inside now' account for un-checks, are canceled tickets counted) that an agent reporting numbers would want.

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%, with each of the three parameters documented including the organizer-optional rule. The description adds no parameter-level detail beyond the schema, so the 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?

Clear verb+resource: fetches live check-in counts for a specific check-in list, and enumerates exactly which numbers are returned (tickets existing, checked in, currently inside), broken down per product/variation. It is distinguishable from pretix_list_checkin_list_positions, which lists individual scans, though it does not name that sibling explicitly.

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?

Usage is implied by the word 'live' and by the aggregate nature of the response, suggesting this is the dashboard-style summary rather than a scan log. However, it never states when to prefer this over listing positions or checking a single ticket, and gives no preconditions.

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