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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false. The description adds useful context beyond those annotations: it is free, keyless, and independently checkable on Base, which informs cost, authentication, and verifiability expectations. No contradiction with annotations exists.

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 compact and front-loaded, starting with what the tool returns before adding verifiability and access qualifiers. Every sentence earns its place—'Free, keyless, read-only' is high-value decision information, and the Base verifiability sentence adds trust context without bloating the text.

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 simple single-parameter read-only tool with a rich output schema and strong annotations, the description is nearly complete. It conveys the input precondition, the kind of data returned, and the trust/cost profile; the only notable gap is not routing agents away from sibling tools like net_subscription_quote.

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?

There is only one parameter and schema description coverage is 100%, so the schema already explains that wallet is the subscriber wallet (0x…) that paid. The tool description repeats this notion but adds no genuinely new detail about the parameter format or edge cases.

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 uses a specific verb ('returns') and names concrete resources: paid months, program budget, asset naming, and fulfillment state. It clearly identifies the tool as a subscription-status lookup, though it does not explicitly distinguish it from the similarly named net_subscription_quote.

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 phrase 'Given a subscriber wallet' establishes a clear precondition and usage context, and the enumerated return values make it obvious when this tool is appropriate. It does not name alternatives such as net_subscription_quote or specify when not to use it, so it misses the top score.

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