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

With no annotations, the description carries the full burden. It usefully discloses the data sources (Blockscout primary, Sourcify fallback) and a pricing constraint (5 free trial calls per signed wallet), but omits what happens when a contract is unverified on both sources, whether the call is read-only, and any output shape.

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?

Two compact sentences with the resource and chain coverage front-loaded and the pricing note appended. No filler, though the pricing note is arguably metadata rather than invocation guidance.

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?

No output schema, no annotations, and five completely undocumented parameters mean the description leaves the agent guessing about how to identify the contract and chain. For a lookup tool with this much schema ambiguity, the description should do considerably more.

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% and none of the 5 parameters (q, chain, address, chainId, contract) are explained in the description. The overlapping address/contract/q and chain/chainId fields are genuinely ambiguous and the description does nothing to disambiguate them or state which are required.

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 verb+resource ('Contract ABI (functions and events)') and enumerates the supported chains and backing data sources, so the tool's purpose is unambiguous. It does not distinguish itself from close siblings such as x402-abi-decode and x402-abi-encode, which an agent may confuse with it.

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 only implied: an agent can infer this is the tool to fetch an ABI before decoding/encoding, but the description never says when to use it versus x402-abi-decode, x402-abi-encode, or x402-contract-scan. No prerequisites or exclusions are stated.

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