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

Annotations only cover readOnly and openWorld; the description adds material behavioral facts the annotations cannot: a per-call price ($0.001 USDC on Base via x402), the failure mode for unpaid calls (PaymentRequired), and the fact that x402 MCP clients handle payment automatically. Arc's USDC-denominated fees are also disclosed.

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 data returned, then the chain nuance, then the payment model. The payment sentence is dense with parenthetical clauses but every clause carries operational information an agent needs.

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 must describe return content — it does, specifying block height, gas price, and three fee-estimate variants. Combined with annotations for safety and the explicit payment/x402 behavior, nothing required for correct invocation is missing.

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 0% for the single 'chain' parameter, so the description must carry the meaning — and it does, naming both valid values and explaining that Arc changes fee denomination to USDC. It omits that the schema default is 'base', leaving the no-argument case unstated.

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 the exact resource (network status) and enumerates what comes back: live block height, gas price, and fee estimates for three transaction types, scoped to Base or Arc. No sibling (address_profile, usdc_balances, verify_usdc_payment, explain_transaction, chainkit_catalog) overlaps this resource, so an agent can select it without inference.

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?

Usage is implied by the content list (call it when you need block height or gas/fee quotes), and the Arc fee-denomination note hints at a chain choice. But there is no explicit when-to-use/when-not-to-use statement and no routing to alternatives such as chainkit_catalog or verify_usdc_payment.

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