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

With no annotations provided, the description carries the full burden. It discloses the 30-day duration, the behavior when a target appears on blacklists ('status flips to alerted'), the optional webhook for push notifications, and the cost ($0.010 USDC via x402). It does not mention renewal, cancellation, or post-subscription error handling, but covers the core behavioral effects and costs.

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 three sentences long, front-loaded with the main action ('Subscribe a wallet or entity for 30-day continuous monitoring'), and every sentence contributes useful information: duration, alert behavior, webhook option, and cost. No redundant or filler content.

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?

Given five parameters and no output schema, the description explains the tool's purpose and key behaviors but omits details about the response format (e.g., subscription ID, status object) and post-subscription lifecycle (cancellation, renewal). It also does not mention whether a subscription can be extended or if there are prerequisites. These gaps make it only moderately complete for a non-trivial subscription tool.

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%, so the schema already documents all five parameters accurately. The description adds minimal semantic value beyond the schema, only implicitly clarifying that 'value' is the target to monitor and webhook_url is for notifications. It does not explain chain or label beyond their existing schema descriptions, so 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?

The description clearly states the verb 'Subscribe' with a specific resource ('a wallet or entity') and a defined scope ('30-day continuous monitoring'). It distinguishes itself from sibling tools like monitor_check (which implies status checking) and compliance_wallet (which likely does one-time checks) by emphasizing ongoing monitoring and alerting.

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 provides clear context for when to use this tool: for continuous 30-day monitoring with alerting on blacklist/status changes. It does not explicitly name alternative tools or say when NOT to use it, but the ongoing vs. one-time distinction is implicit in the wording, giving enough guidance without explicit exclusion.

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