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

Annotations already cover the safety profile (readOnly, non-destructive, closed-world), and the description adds substantial context beyond that: exact cost (0.0005 USDT per 100 rows prepaid, 0.01 USDC per request via x402), the required payment prerequisite (orbitpay_info), and an out-of-band HTTP route. This is well above the bar for a paid tool.

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?

Front-loaded with purpose, followed by the payment model and a concrete route; every sentence serves invocation. The pricing detail is denser than strictly necessary but earns its place as a cost prerequisite.

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?

Payment and access mechanics are fully covered and no output schema exists to explain, so the return side is fine. But for a 5-parameter tool with 0% schema description coverage and a nested filters object, the complete absence of parameter semantics leaves a real gap.

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 0% for all 5 parameters (to, from, limit, cursor, and a nested filters object), and the description adds no parameter meaning at all — no date format for from/to, no cursor semantics, no filter key documentation. With 0% coverage the description must compensate, and it does not.

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 names a specific resource and scope: 'Premium Wanchain economics time series (supply, fees, and related metrics over time)'. This is distinguishable from siblings like orbitpay_token_supplies (single-metric) and orbitpay_crosschain_history (different domain), so an agent can tell why to pick this 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?

It explains the two payment pathways clearly (prepaid credit vs x402 per-request) and points to orbitpay_info for signing steps, which is genuinely actionable invocation guidance. However, it never states when to use this tool versus sibling economics/history tools, so tool-selection guidance is only implied.

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