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

No annotations are provided, so the description carries the full burden, and it does well: it discloses the x402 payment requirement, the exact cost ($0.05 USDC on Base), that the alert is one-time, and that server-side evaluation runs every 5 minutes. It stops short of covering failure modes (insufficient funds, invalid symbol) or whether the alert expires unfulfilled.

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?

Three sentences, front-loaded with the cost/paid nature before the workflow, and every clause earns its place: cost, polling partner, return value, and evaluation cadence.

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?

There is no output schema, so the description correctly supplies the key return value (alertId) and the cadence of evaluation. It is sufficient for an agent to call and follow up on this tool, though it omits edge cases like what happens when a payment fails or an alert expires.

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 100% with three well-documented parameters including an enum for condition, so the schema already does the heavy lifting. The description adds no per-parameter syntax or format detail beyond what the schema provides, making the baseline 3 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 and resource ('Register a one-time price alert for a cryptocurrency') with clear scope (one-time, single symbol/condition/threshold). It is immediately distinguishable from the sibling check_price_alert, which it explicitly positions as the follow-up polling tool.

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?

Gives an explicit two-step workflow: register here (paid), then poll check_price_alert (free) with the returned alertId. It names the alternative tool and the condition that selects it, so the agent knows exactly when to call each.

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