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

With no annotations, the description carries the full burden and delivers notably rich context: it scans 2-leg and 3-leg paths, returns net profit after fees, caches data for 30s, costs $0.0200 USDC per call, and uses an x402 POST endpoint for live data. Caching, pricing, and payment model are all disclosed. It could say more about rate limits or error behavior, but this is strong for a no-annotation tool.

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 sentences, front-loaded with the core scan-and-return behavior, followed by the operational pricing/endpoint details. It is dense with a URL and pricing block but every element is functional; little waste.

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 conveys what is returned (best opportunity with net profit after fees), the data freshness (30s cache), and the call cost. That is sufficient for an agent to decide whether to invoke it.

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 input schema has zero parameters, so there is nothing to document and the baseline of 4 applies. The description correctly implies a parameterless invocation.

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: scanning multiple sizes and paths (2-leg and 3-leg) on Jupiter and returning the best net-profit opportunity. This is clearly distinct from price-oriented siblings like quote and harga. It stops short of naming a sibling to differentiate explicitly, but the purpose is unambiguous.

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 explains what the tool does but never says when to prefer it over siblings like quote or yield-defi, nor any prerequisites or exclusions. There is no when-to-use/when-not guidance beyond the implied arbitrage scenario.

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