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

With no annotations, the description carries the full burden. It does disclose cost ('0.05 USDC per call via x402') and the shape of the returned data, which is useful. However, it omits whether the fee is per chain, whether paymentProof is reusable, rate limits, and error behavior — all material for a paid tool.

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?

Five compact sentences, front-loaded with what the tool returns and followed by usage, chain coverage, and cost. There's little waste, though the sentences could be combined and the sibling overlap left unaddressed.

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?

For a 2-parameter read tool with no output schema and no annotations, the description covers what is returned, which chains, and the payment cost. It leaves gaps around return structure, per-chain pricing nuances, and why an agent should pick this over gas_price or multi_chain_gas.

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%, so the baseline is 3. The description's 'Covers Solana, Base, BSC and Ethereum' loosely maps to the chain enum values, and the payment model is described at a high level, but the schema already documents both parameters and the 402 flow in detail.

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 a specific resource and its contents: gas price tiers (high/average/low), estimated confirmation times, MEV-protection fee and native token USD price, plus supported chains. It's clear what the tool returns, but it doesn't distinguish itself from sibling tools that appear to do the same thing (gas_price, multi_chain_gas), which is a requirement for a 5.

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?

It gives one usage scenario — 'Agents use this to set optimal priority fees for snipe transactions' — which implies when to reach for it. But it never states when not to use it or how it differs from the gas_price and multi_chain_gas siblings, so the agent has no explicit routing guidance.

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