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

With only 'false' annotation flags, the description carries the behavioral burden, and it does so by specifying the API key format, location, and the structured error contract. It doesn't describe post-creation side effects or whether the alert starts immediately, but this is a modest gap.

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 action is front-loaded in the first sentence, followed by focused sentences on parameter choice, requirement, auth prerequisite, and error output. Each clause carries semantic weight, though the paragraph is slightly longer than strictly necessary.

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?

Since the tool has an output schema, the definition doesn't need to describe successful return values. The description covers authentication, the mandatory conditional fields, API key source, and error structure, giving an agent all crucial non-obvious context for a successful call.

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 schema already covers 100% of parameter details, giving a baseline of 3. The description adds value beyond the schema by grouping the threshold-free flags separately from the numeric threshold settings and by introducing the cross-field requirement that at least one is mandatory.

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 verb 'Create' combined with 'price alert' and 'for a product' states exactly what the tool does. The subtle distinction with siblings like update_price_alert is immediately obvious from the verb choice.

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 explicitly explains the two operating modes: threshold-free notify_on_drop/notify_on_rise vs numeric min/max_threshold_price, and states the crucial 'at least one of those four settings is required' constraint. It provides clear create-context, though it doesn't explicitly name update_price_alert as the alternative for modifying existing alerts.

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