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

The description discloses key behaviors: the hold is temporary, nothing is paid, a checkout URL is returned, and the hold expires on its own. No annotations are provided, so the description carries the full burden. It lacks details on error conditions or response format, but the core behavior is well-covered.

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 two sentences long, front-loading the main purpose and following with critical behavioral context. Every sentence adds value, with no redundancy or filler.

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 the tool's simplicity (2 required params, no output schema), the description covers purpose, usage, and behavior well. It mentions the returned checkout URL but not its structure; still, the information is sufficient for correct selection and 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 coverage is 100% with parameter descriptions, so baseline is 3. The description adds context (max 10 tickets/ticket types) but does not significantly enhance parameter understanding beyond the schema's existing descriptions.

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 specifies the verb 'hold' and resource 'tickets', and distinguishes from siblings like create_booking or create_checkout by emphasizing it's a temporary hold, not a purchase.

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 and when not: 'Only works for events this site sells directly — for events sold elsewhere (Sympla, Ingresse, Sesc), use the event's own ticketUrl instead.' It also provides constraints (max 10 tickets and 10 ticket types) and clarifies the temporary nature.

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