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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds genuinely non-obvious context the annotations do not: that names, symbols, tags and method names come from whoever deployed/verified the contract and are wrapped as untrusted, which is a meaningful security caveat. It stops short of covering failure modes (non-token address, unverified contract).

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 sentences: the first front-loads the return payload, the second delivers the untrusted-data caveat. Nothing is redundant, though the field list is dense and the description opens with a noun phrase rather than an action verb.

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 return-value burden and does it well by enumerating the fields. Combined with 100% schema coverage for the sole parameter and safe-read annotations, an agent has nearly everything needed; only edge-case behavior (invalid or non-token address) is unstated.

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?

There is a single parameter and schema description coverage is 100%, so the schema fully documents the 0x-prefixed 20-byte address. The description adds no further semantics about the address (e.g. that it is the token contract rather than a wallet), so the baseline of 3 applies.

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 resource (a token) and enumerates the exact fields returned — name, symbol, token standard, decimals, supply, holder count — which is far more specific than the title 'Token info'. It implicitly distinguishes itself from siblings like explorer_token_holders, explorer_token_balances and explorer_token_transfers by scoping to metadata only, though it never names them or states a verb explicitly.

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 call for token metadata versus balance/holder/transfer listings, because the description enumerates what it returns. There is no explicit when-to-use statement, no exclusions (e.g. non-contract addresses, unverified tokens), and no routing to alternatives.

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