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

Annotations cover safety (readOnly, non-destructive), but the description adds material context beyond them: cost of $0.01/call via x402 USDC or card key, first 25 free, failed calls free, 404 uncharged, and that repeats are charged so the call is effectively non-idempotent for billing. This billing/repeat-charge disclosure is exactly the kind of behavior an agent cannot infer from annotations.

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?

Dense but front-loaded: purpose and returned fields come first, then routing guidance, then input format, then pricing. Every clause is informative, though the pricing sentence is long and could be split for readability.

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?

With no output schema, the description carries the burden of describing return values and does so comprehensively (status, gas, price, fee, logs, created contract). Combined with input format, error behavior, and cost model, an agent has everything needed to invoke and interpret the result.

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 the baseline is 3, but the description adds a concrete constraint restatement (0x-prefixed 64-hex hash) plus a worked example hash, which helps an agent format input correctly. No further semantic detail is possible for a single opaque hash parameter.

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?

States a specific verb and resource ('Transaction receipt on Sonic') and names the underlying call (eth_getTransactionReceipt), then enumerates exactly what is returned: status, gas used, effective gas price, fee in S, log count, contract created. It explicitly distinguishes itself from the sibling sonic_tx by use case.

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?

Gives a clear positive trigger ('use to confirm a payment or call went through') and a clear alternative with its condition ('for sender, value and calldata use sonic_tx'). It also documents the failure mode: pending or unknown hash returns 404 and is uncharged.

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