Ethereum: ethSwapQuote

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint, covering safety and idempotency. The description adds that crypto is volatile and prices must be fresh, which is a behavioral trait beyond annotations. No contradiction.

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?

Three sentences: purpose, warning, parameter hint. No fluff, every sentence adds critical information. Front-loaded with purpose, followed by actionable guidance.

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?

The description does not explain the output format (structure of price and quote). With no output schema, agents lack details on what the response contains (e.g., slippage, gas, expiration). For a swap quote tool, this is a notable gap, though the purpose is broadly communicated.

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 covers all 3 parameters with descriptions (100% coverage). The description adds value by specifying the native ETH address constant, which is not in the schema. This helps agents correctly fill the fromTokenAddress for ETH swaps.

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', using specific verb (Get) and resource (price and swap quote). The name includes chain (Ethereum), distinguishing it from sibling tools for other chains like baseSwapQuote or bscSwapQuote. No ambiguity.

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 advises to 'ALWAYS fetch fresh prices' due to volatility, and provides a specific parameter hint for native ETH address. It does not explicitly state when not to use this tool, but the context of fetching fresh quotes is clear enough for an agent.

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