evm_swap

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

Discloses beyond annotations: returns UNSIGNED calldata, server never touches funds, 0.3% routing fee, ERC20 approval requirement. No contradiction with annotations (readOnlyHint=false, destructiveHint=false).

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 dense sentences plus a brief note. Front-loaded with key info. Every word 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?

Complete for a swap tool with rich annotations. No output schema but explains return value as {to,data,value}. All 7 parameters covered in schema; description addresses critical behavioral aspects.

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 coverage is 100%, but description adds value by clarifying amount vs amountRaw (human vs base units) and implicit approval requirement for ERC20 inputs. Baseline 3 exceeded.

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 specific verb 'Build' with resource 'NON-CUSTODIAL EVM DEX swap via KyberSwap aggregator' and lists supported chains. It clearly distinguishes from sibling tools like sol_swap or hl_build_order by specifying EVM and non-custodial nature.

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?

Provides clear context: non-custodial, sign with own wallet, ERC20 needs prior approval, 0.3% fee. Does not explicitly list when not to use, but the details implicitly guide correct usage.

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