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

The description adds substantial behavioral information beyond the annotations: the alert sends email, re-saving updates and re-arms the alert, there is a hard limit of 10 active alerts, and OAuth with the 'alerts' scope is required. This gives an agent important side-effect and precondition knowledge that annotations do not convey, and it does not contradict the annotations.

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 five concise sentences with the core behavior first, followed by memorable examples, lifecycle semantics, limits, and prerequisites. Every sentence carries distinct information and there is no filler or restatement of the schema.

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 mutation tool with no output schema, it covers all prerequisites needed to call it correctly: store_id resolution, auth scope, the maximum number of alerts, and what re-saving does. An agent has enough to decide when to use it and how to construct a valid 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?

The input schema already documents all three parameters in detail with 100% coverage, so the baseline is 3. The description adds useful operational framing—store_id provenance, re-saving semantics, and alert limits—but does not materially extend the parameter-level definitions already present in the schema.

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 opens with a clear verb-plus-resource: 'Creates or updates an alert' and specifies exactly what triggers it (cashback rate or gift card discount reaching a threshold. The examples like 'alert me when Nike cashback hits 10%' remove ambiguity, and the create/update operation is clearly distinct from sibling get/remove alert tools.

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 provides explicit use cases and a direct pointer to get_stores_by_name for resolving a store_id, and notes the required OAuth scope. It stops short of explicitly contrasting this tool with get_my_alerts or remove_store_alert, but the usage context is clear enough for an agent to select it.

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