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

With no annotations provided, the description fully discloses behavioral traits: the hold is temporary, not paid, expires on its own, and requires human checkout via the URL. It also states limits (max 10 tickets and 10 ticket types). This goes well beyond the input schema.

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?

The description is concise and front-loads the main action. It efficiently packs important behavioral notes and limits. However, the list of limits (max tickets and types) could be slightly better structured, but overall it is very good.

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?

Given no output schema, the description mentions returning a checkout URL, which is sufficient. It covers event type restrictions, hold behavior, limits, and prerequisites. For a tool with 2 parameters and no nested objects, this is complete.

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% with descriptions for both parameters (event_slug and tickets). The description does not add significant meaning beyond the schema, as it repeats that tickets come from get_event_tickets and quantity must be at least 1, which are already in the schema. Baseline score of 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?

The description clearly states the tool's purpose: 'Hold tickets for an event sold through this site (Wix Events) and return a checkout URL.' It uses a specific verb ('Hold') and resource ('tickets'), and distinguishes from siblings by noting that for events sold elsewhere, users should 'use the event's own ticketUrl instead.'

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 description explicitly states when to use the tool (for events sold directly through this site) and when not to (for events sold elsewhere, use ticketUrl). It also provides contextual guidance on the temporary nature of holds and expiration. However, it does not explicitly reference sibling tools like create_checkout or get_availability as alternatives.

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