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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds meaningful context beyond that: data is fetched live via eth_call (not cached), and supply is returned in both raw and formatted form. It does not mention failure modes for non-contract addresses, but the added value is real.

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 tight sentences, front-loaded with the resource and output list, with the disambiguation clause at the end. Every phrase earns its place.

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 compensates by enumerating the returned fields, and annotations cover the safety profile. Nothing an agent needs to select or call it 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?

There is a single parameter with 100% schema coverage, including a regex pattern and description, so the schema carries the full burden. The description adds nothing about the token address format, making baseline 3 appropriate.

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?

Names a specific resource (ERC-20 token contract on Base mainnet) and enumerates exactly what it returns: name, symbol, decimals, and total supply in raw and formatted form. The 'facts only, no price or recommendation' clause cleanly separates it from price-oriented siblings like solana_token_price.

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?

The scope statement ('on Base mainnet') and the 'no price or recommendation' exclusion implicitly tell an agent when this tool is appropriate and when to reach for a price tool instead. It stops short of naming an explicit alternative or stating prerequisites, but the context is unambiguous.

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