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

With no annotations, the description carries the full behavioral burden and does so: read-only public chain data, no wallet action or custody, a payment challenge bound to a specific HTTP endpoint rather than mcp://, and retry semantics for identical authorized arguments. That is auth, safety, and error-recovery context an agent could not derive from structured fields.

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 capability and its outputs before the sibling distinction and the payment/retry note. Every sentence carries information, though the payment-challenge sentence is dense and slightly opaque in phrasing.

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 characterize returns — it does by enumerating the profile fields. It also covers the payment/credential path and retry behavior, leaving only edge cases such as unsupported chains or failure modes unaddressed.

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 100% and there is a single parameter, so the schema already documents the address format and its routing hint. The description restates 'public Base or EVM address' without adding syntax or format detail beyond what the schema provides, which is the baseline-3 case.

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 and resource ('Inspect a public Base or EVM address') and enumerates the returned evidence: address type, holdings, token/NFT metadata, proxy evidence, activity, and a derived label. It also explicitly separates itself from the sibling `enrich`, which handles company domains, so an agent can route without opening either schema.

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 names the alternative tool explicitly ('Use `enrich` for a company domain') and states the discriminating condition ('the two tools accept different identifiers and return different evidence'). It also gives a retry directive for the authorized-arguments case, leaving little to inference.

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