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

Despite readOnlyHint=true already signaling non-mutation, the description adds valuable context: the response contains unsigned transaction data and the tool never signs or submits it. This clarifies the exact boundary of the tool's behavior.

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 concise sentences with no filler. The primary action is front-loaded, and the safety qualifier about not signing or submitting 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?

The combination of a fully documented schema, read-only annotation, and a description that clarifies the unsigned nature of the response is sufficient for an agent to invoke the tool correctly. It lacks explicit routing among sibling quote tools, but that is not a critical gap here.

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 the schema already documents all parameters. The description adds domain framing ('EVM source asset', 'Base USDC') but no new parameter-level detail beyond what the schema provides.

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 uses a specific verb ('Quote') and identifies the resource: a live Relay route from an EVM source asset into Base USDC. It clearly states the tool's function, though it does not explicitly name a sibling tool to differentiate it from peer_cash_estimate or peer_quote.

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 implies usage—call this when you need a quote for a Relay route—but does not state when to use it versus alternatives or when not to use it. No explicit exclusion or naming of sibling tools is provided.

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