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

Annotations already establish readOnly/idempotent/non-destructive, and the description adds meaningfully: it is free, requires no wallet or payment, and returns exact received amount, fee breakdown, and ETA. It does not repeat the safety traits, so it earns above baseline, though no caveats on route availability or staleness are given.

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?

Two tight sentences with the key qualifier 'Free' front-loaded and no filler. Every clause (cost, output, fee breakdown, ETA, no wallet) conveys distinct information.

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 an output schema present, the description need not document return values, and the annotations cover the safety profile. It is complete enough to invoke correctly, missing only edge-case guidance such as behavior when a route is unavailable.

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% with descriptions for all four parameters (including ref's 20% fee share and amount semantics), so the schema already carries the load. The description only reinforces the 'exactly amount received' semantics, which the schema already states.

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+resource (quote for bridging USDC between Base and Arc) and names the mechanism (Liquid Bridge). Distinguishes it from siblings like bridge_prepare_payment and bridge_routes by clarifying it is a read-only price check, not a payment or route listing.

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?

'Free. No payment, no wallet needed' makes clear this is the safe pre-flight step before committing to a payment, which implicitly routes the agent here before bridge_prepare_payment. It does not explicitly name alternatives or a when-not condition, so it falls short of a 5.

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