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

Annotations already declare this a non-read-only, non-destructive, idempotent operation, so the safety profile is covered. The description adds value beyond that: it discloses the actual side effect (an alert is created on the linked account), the event that fires it (a reservation opening), and the auth precondition (pairing key). It stops short of saying how alerts are delivered or that remove_watch cancels them.

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 filler, and the core effect ('creates an alert... fires when a reservation opens') is front-loaded ahead of the prerequisite. Every clause earns its place.

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?

For a 3-parameter tool with no output schema, the description covers the action, its trigger, and the account prerequisite, and annotations carry idempotency and non-destructiveness. The main gap is that with no output schema it never hints at what the call returns (e.g., a watch id or confirmation), which an idempotent create tool arguably should mention.

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 67%, with 'date' documenting the 180-day window and 'restaurant' giving a slug example, but 'party_size' has only min/max bounds and no prose. The description only restates 'the given date and party size' and adds no syntax, format, or matching semantics (e.g., fuzzy name matching, slug lookup behavior) beyond the schema. Baseline 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?

States a specific verb ('Creates an alert') and a precise resource ('a reservation opens at a Walt Disney World restaurant'), with the trigger condition spelled out. The dining-restaurant scope cleanly separates it from the sibling watch_ride, so an agent can choose between them without opening either 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?

It supplies a real prerequisite ('Requires a linked SupaPark account (pairing key)'), which is genuinely useful context for whether the call can succeed. However, it never says when to prefer this over alternatives such as watch_ride, list_my_watches, or remove_watch, nor any when-not-to-use condition. Usage is implied rather than guided.

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