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

The description discloses that quotes are live, measured per source chain, refreshed every 10 minutes, and includes the X1 bridge minimum of 11 USDC. It also notes a CCTP mention. With no annotations provided, the description carries the burden and does a good job of setting expectations about data freshness and constraints, though it doesn't detail the exact output format or failure modes.

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?

The description is a single, information-dense sentence that front-loads the core purpose (USDC onto Arc) and then adds specifics. It's slightly long but every clause adds value: source chains, LI.FI, what's measured, refresh rate, X1 minimum, and CCTP note. The usage guidance at the end is a bit tacked on but not redundant.

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 zero-parameter tool with no output schema, the description covers the key context: what it does, how it works (LI.FI), what data it provides (cost, time, what arrives), freshness (10 minutes), and a usage scenario. It doesn't explain how to interpret the quote or what 'claim at the faucet' entails, but those are likely covered by sibling tools (arc_faucet_claim).

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?

The tool has zero parameters, so the description doesn't need to explain parameter semantics. The baseline for 0 params is 4, and the description adds context about what the tool measures and returns, which is sufficient.

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 clearly states the tool's purpose: it provides live USDC bridge quotes to Arc (eip155:5042) from multiple source chains via LI.FI, including cost, time, and what arrives. It also mentions the X1 path and CCTP note, distinguishing it from generic bridge tools like bridge_assets or get_onto_x1.

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?

The description explicitly says 'Use it to bring an agent or a person to Arc from wherever they are, then claim at the faucet,' giving clear context for when to use it. It doesn't explicitly state when not to use it or name alternatives, but the sibling list includes bridge_assets and get_onto_x1, and the description's specificity about Arc and USDC implies the alternative scenarios.

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