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

With no annotations, the description carries the full burden. It discloses key behaviors: 30-day duration, status flip to 'alerted', optional webhook, and cost ($0.010 USDC). However, it omits details like expiration/renewal behavior, cancellation, or what the initial response contains.

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, each delivering distinct value: subscription action, alert behavior, webhook and cost. No fluff, front-loaded with the primary verb and resource.

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 description covers the core transaction: what is monitored, duration, alert status, and cost. However, with no output schema, it fails to clarify the return value (e.g., subscription ID) or post-subscription management (cancel/renew). This is a notable gap for a paid 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 coverage is 100%, so parameters are fully documented. The description adds context about wallet/entity (type) and webhook_url, but does not exceed the schema for chain or label. This matches the baseline of 3 when the schema does the heavy lifting.

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 tool's function: 'Subscribe a wallet or entity for 30-day continuous monitoring.' This is a specific verb (subscribe) with a resource (wallet/entity) and scope (30-day), distinguishing it from siblings like monitor_check or compliance_watchlist.

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 implies use for ongoing monitoring over a fixed period, with alerts on blacklist hits, and optional webhooks. It does not explicitly name alternatives (e.g., monitor_check for one-time checks), but the context is clear enough that an agent can infer when to use it.

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