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

With no annotations, the description carries the full burden and does disclose key traits: nothing is signed or sent (non-mutating), fees are levied through a CCTP router at 10 bps with a 0.02 USDC minimum, and the return is a set of approve + bridge calls. Auth requirements and any rate limits are still unstated, keeping it from 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?

Two dense sentences, front-loaded with the purpose and the API route before the behavioral and parameter detail. Every clause carries information; it is compact without being cryptic.

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 planning tool with no annotations and no output schema, the description supplies the essential context: what it returns, that nothing is signed, and the fee model. Remaining gaps are sender/recipient/speed semantics and any auth notes, but overall it is sufficient for correct invocation.

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% across 6 params, so the description must compensate. It covers src_chain_id/dst_chain_id (with 8453 Base and 5042 Arc examples) and the amount unit (USDC smallest units, 6 decimals), but sender, recipient, and speed enum remain undocumented in both schema and description.

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?

Specific verb (Plan) plus resource (USDC transfer across chains), with the API route named and the exact output framed as 'the exact approve + bridge calls... the fees and what arrives.' The 'plan / nothing is signed' framing cleanly distinguishes it from execution siblings like taifoon_transfer_attest.

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 phrase 'Nothing is signed or sent' implies this is the pre-execution dry-run, which helps an agent infer when to reach for it. However, no sibling is named as the alternative (e.g. taifoon_transfer_attest for the actual signed transfer), so the when-to-use routing is left to inference.

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