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

With no annotations, the description carries the full burden, and it does a good job: it discloses that the transaction is unsigned, shows the verification block fields, and warns to verify before signing. It could go further by noting that it performs no on-chain mutation itself, but 'unsigned transaction' and the sign-only-if-allowlisted warning make the key behavior clear.

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 compact and front-loaded: purpose, return format, verification block, and signing warning all appear in two sentences. Every sentence adds essential information and there is no filler.

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?

This is a security-sensitive, multi-chain tool with no output schema and no annotations, yet the description leaves out key context such as the prerequisite of calling get_swap_quote, the meaning of minBuyAmount and approvalTarget, and how to handle amount units. The verification warning is valuable, but overall the description is incomplete for correct usage.

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 only 33%, and the description does not compensate. It does not explain the units of 'amount', the meaning of 'slippageBps', or how the source, buy, and sell fields relate to the quote. The nested buy/sell objects and the native token convention are only covered inside the schema, not in the description.

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 identifies the verb 'Build' and the resource: 'an unsigned transaction for a quoted swap.' It also distinguishes itself from get_swap_quote by focusing on transaction construction, and from plan_route by returning EVM/Solana unsigned transaction data.

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?

It clearly states that the tool is for a quoted swap, so the agent knows it must be preceded by quote generation. It provides an explicit safety precondition: sign only if routerAllowlisted is true and addresses match get_meta's allowlist. It does not explicitly enumerate when not to use it relative to siblings, but the 'quoted swap' context is sufficient.

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