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

Beyond the annotations it discloses error semantics (400 malformed, 404 no code, both uncharged), pricing ($0.01/call, first 25 free, failures free), and that repeats are not free — which explains the idempotentHint=false rather than contradicting it. It also restates the no-state-change property of a read/compute 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-loads purpose, then alternative, then failure modes and cost — a sound order with little filler. It is dense (pricing plus error codes plus mechanism list in a few sentences) and could be tightened, but every clause carries operational value for an agent deciding to call it.

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 single-parameter, annotated, no-output-schema tool, the description covers what is returned (the implementation and the kind found), when to use it, what failure responses look like, and what it costs. Nothing an agent needs to invoke it correctly 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?

Only one parameter and schema coverage is 100% ('0x contract address'); the description adds an example address confirming the expected format but no syntax or constraint details beyond what the schema already conveys. Baseline 3 is correct.

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 ('find the implementation behind a proxy contract on Optimism') and enumerates the detection mechanisms (EIP-1967, beacon, admin, UUPS/EIP-1822, OZ layout, EIP-1167). The chain prefix in the name is reinforced in prose, so it is clearly distinguishable from eth_proxy/arb_proxy/base_proxy/polygon_proxy siblings.

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 an explicit when-to-use ('before trusting or decoding a contract whose code can be swapped by its admin') and names the escalation path ('for a fuller risk verdict use contract_risk'). Nothing is left to inference about the decision boundary.

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