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

Beyond the annotations, the description discloses important behavior: creation is gated by alerts:write and a paid plan, email requires explicit human consent, and payment is not treated as delivery consent. It also notes that the website's validation and limits apply. It does not explain duplicate-create or non-idempotent behavior, which keeps it from a 5.

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 front-loaded with the action and its main inputs, followed by authorization and consent constraints. It is compact and mostly free of waste, though "using the website's validation and limits" is somewhat vague and could be sharper.

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?

The purpose, authorization requirements, plan requirement, and email-consent constraint are covered, and an output schema exists so return values need not be explained. Still, for a 9-parameter tool with 0% schema description coverage, the description leaves meaningful gaps around browser, timezone, and the exact semantics of several fields.

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 0% across 9 parameters, so the description must carry parameter meaning. It mentions theatres, formats, triggers, cadence, and email consent, but omits movie, browser, and timezone, and does not explain enum values such as on-sale-near or the default cadence. Partial compensation is present, but substantial gaps remain.

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 states a specific verb and resource: "Create a movie follow." It also lists the main configurable dimensions (theatre IDs, formats, triggers, cadence), making the operation clear. It does not explicitly contrast itself with sibling alert-management tools such as update_alert, list_alerts, or delete_alert, so it falls short of the top score.

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 supplies useful prerequisites: alerts:write, a paid plan, and explicit email consent. However, it gives no explicit guidance on when to choose create_alert versus update_alert, set_reminder, or other sibling tools, and it does not state when this tool should not be used.

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