arc_yield

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

With no annotations, the description carries the full burden and does so well: it discloses the 15-minute refresh cadence, the $0.003 price, the accepted payment rails (USDC on Arc/Base/Solana, XNT on X1), the two-step x402 handshake (call for terms, sign, re-call with payment), and that withdrawal depth is read on-chain at the current block. These are exactly the operational facts an agent needs before invoking it.

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?

Purpose is front-loaded and no sentence is purely filler, but the payment sentence is dense and run-on, packing price, four currencies and the two-call flow into one long line. Slightly more structure would improve scannability without losing content.

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 or annotations, the description compensates by describing the returned fields, freshness and payment/auth requirements, so an agent can call it correctly. It omits failure/error behavior and any notion of result size or pagination for the full board, which is a minor remaining gap for a plain two-parameter tool.

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 adds value beyond the schema text by explaining that `vault` narrows the whole board to a single address and by spelling out the `payment` workflow (first call yields terms, second call completes the purchase). This meaningfully extends the terse schema descriptions.

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 and resource: it yields lending-vault metrics on Arc for the vaults Circle Earn Kit lists (Morpho Vault V2), and enumerates the exact data points returned (rate, size, realizable withdrawal, lending destinations, 24h trail). This is distinguishable from generic siblings like arc_pools or vault_heartbeat without opening the schema.

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 opening clause 'before you deposit' establishes the primary when-to-use condition, and the payment instructions give clear procedural context. It does not, however, name alternative siblings (e.g., arc_pools) or state when NOT to use it, so guidance is clear but not complete.

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