Ethereum: ethSwapQuote

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

Annotations already cover safety (readOnlyHint, destructiveHint, etc.). The description adds useful context about volatility and the native ETH address but does not disclose other behaviors like rate limits or response format. With annotations present, this is adequate.

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 exceptionally concise: two sentences that front-load the core purpose and then add critical usage tips. No wasteful words, every sentence earns its place.

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?

While the description is clear for its simple purpose, it lacks information about the return format (e.g., structure of the quote). No output schema exists, so the description should ideally describe what the agent can expect. Missing this reduces completeness for such a 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 description coverage is 100%, so baseline is 3. The description adds value by specifying the native ETH address (0xEeeee...), which is a practical hint for the fromTokenAddress parameter, improving usability beyond the schema.

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 'Get current USD price and swap quote for Ethereum tokens,' specifying a specific verb and resource. It distinguishes from sibling tools for other chains (e.g., baseSwapQuote) by explicitly mentioning Ethereum.

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 includes a strong usage hint: 'ALWAYS fetch fresh prices - crypto is volatile,' guiding the agent to avoid stale data. It also provides the native ETH address. However, it does not explicitly exclude alternatives or specify when-not to use.

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