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

Goes well beyond the annotations by disclosing the 422 outcome for a non-ERC-20 address (and that it is uncharged), the $0.01/call x402 pricing with 25 free calls, and that repeated calls are billed — which explains why idempotentHint is false despite the read-only nature. It also states data is read live from the 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?

Front-loaded with purpose, then usage, then input format, then cost — a sensible ordering. It is dense and the pricing clause is long, but every sentence carries information an agent needs (cost, failure behavior, sibling routing) rather than filler.

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, and the description compensates by enumerating the returned fields. Combined with error semantics, cost, and the sibling alternative, nothing material is missing for a single-parameter read tool.

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 coverage is 100% and the schema already says the parameter accepts a ticker or a 0x address, so the description's restatement is redundant; however the concrete example address and the 422 behavior for non-ERC-20 contracts add real semantic value about what the input will and won't resolve to.

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 plus the exact fields returned ('name, symbol, decimals and total supply of an ERC-20 token contract on Linea'), and explicitly contrasts itself with linea_token_balance. An agent can distinguish it from the ~180 sibling tools 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?

Gives two concrete use cases ('identify an unknown token address', 'format raw amounts') and names the alternative tool with the condition that selects it ('for a holder's balance use linea_token_balance'). No inference required.

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