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

Annotations only declare readOnlyHint and openWorldHint; the description adds substantial behavior beyond that — the $0.004 USDC x402 cost model, that failed calls are free, the quote-then-sign payment flow via the `payment` param, and a free tier of 3 calls/day. This is exactly the kind of cost/auth context annotations cannot carry.

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 purpose and payment terms, and organized into clear labeled sections. Mild redundancy: the warning list (owner, upgradeable, mint/pause/blacklist/fees, Solana mint/freeze authority) is stated twice, once inline and again under 'Returns'.

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 fully covers the return contents in plain language, plus payment flow and free-tier limits. An agent has everything needed to quote, pay, call and interpret the result.

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 schema already documents all three params including the chain enum and default. The description restates token/chain meaning and defaults, adding little beyond the structured fields, so the baseline 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?

States a specific verb and resource ('Check a token') plus scope (which chains, what is returned: identity, USD price, liquidity, chain-read warnings). It distinguishes itself from siblings by explicitly contrasting with token_info and pretrade_check.

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' trigger (before buying, accepting or sending an unfamiliar token) and a 'Use instead' section naming pretrade_check for sized trades and token_info for basics only, with the differentiator for each. No inference required.

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