Live gas / fees

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

Annotations already declare readOnlyHint and openWorldHint, lowering the burden, and the description usefully adds that data comes from public RPCs (implying no auth) and that values are 'live'. It does not mention rate limits, caching, or failure modes when an RPC is unreachable, keeping it short of a 5.

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?

A single front-loaded sentence that opens with the core action ('Live fees from public RPCs') and then branches by chain tier using parallel semicolons. Dense but every clause carries information; slightly long for a one-sentence description but no 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?

With no output schema, the description takes on return-value disclosure and does so adequately by naming the fields returned (base fee, priority tips, native + USD cost, sat/vB, priority fee). It stops short of describing response shape or units for the EVM USD figure, but nothing critical for invoking the tool 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 0%, so the description must carry the load. It partially does: 'cost in native token + USD for a given gas amount' explains the purpose of gasUnits, and the per-chain tiers anticipate the chain enum. However it never states that gasUnits is EVM-only/irrelevant for bitcoin and solana, nor that chain is required.

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 states a specific verb+resource (retrieve live gas fees) and enumerates the per-chain semantics: EVM base fee + priority tips via eth_feeHistory with native/USD cost, Bitcoin sat/vB, and Solana priority fees. It is clearly distinguishable from every sibling (get_chain, decode_transaction, convert_units, etc.), none of which return fee data.

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?

Usage context is implied by the chain-specific breakdown (an agent can infer it should pass 'bitcoin' for sat/vB and 'solana' for priority fees), but there is no explicit when-to-use/when-not statement and no named alternative. With no sibling tool competing for this job, the omission is not harmful, so an implied-usage 3 fits.

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