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

Annotations only declare readOnlyHint and openWorldHint. The description adds information they cannot carry: the x402 payment model ($0.002 USDC per call, failed calls cost nothing, first 3 calls/day free, call without `payment` to get a quote), data freshness ('read live from the chain'), and the limits of what is returned versus crypto_market_pulse.

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-loaded with the core verb/resource, then pricing, routing, params and returns in a scannable order. It loses a point for mild duplication: 'Use it to confirm what an address actually is before acting on it' and 'When to use: ... before acting on it' say the same thing twice.

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, but the description enumerates the return fields itself, and it covers the payment/quote flow, chain options and sibling routing. Nothing needed to invoke this tool 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?

Schema description coverage is 100%, so the baseline is 3. The description restates the token and chain parameters (including the 'base' default) but says nothing about the `payment` parameter beyond the separate pricing paragraph, adding marginal meaning over the schema.

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 ('Look up a token on Base, Ethereum (ERC-20 contract) or Solana (SPL mint)') and enumerates the exact fields returned (name, symbol, decimals, total supply, Solana authorities). It also names the sibling tools it is not (token_check, token_price), so an agent can route without opening the 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?

Contains an explicit 'When to use' line ('You have a token address and need to know what it is before acting on it') and an explicit 'Use instead' line directing safety/liquidity queries to token_check and price queries to token_price. Both the trigger and the alternatives are spelled out.

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