Swap Tokens (EVM)

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

Annotations already declare destructiveHint=true and readOnlyHint=false, and the description is consistent with those. It adds useful behavioral context by explaining that the swap uses the user's Monei wallet, that routing is automatic based on provided fields, that user confirmation is required, and that a transaction hash is returned. This goes beyond the annotation flags without contradicting them.

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 well-structured and front-loaded with the purpose and routing logic, followed by preconditions, Args, Returns, and Examples. The length is justified by the tool's complexity and lack of an output schema. However, the Args bullet list partly repeats information already in the input schema, and the chainId list in the description omits Scroll and Lisk, so it is not perfectly lean.

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?

For a 5-parameter mutating swap tool with no output schema, this description is complete: it specifies route rules, preconditions such as balance verification and user confirmation, slippage default, supported chains, return shape with txHash, and illustrative examples. An agent can determine how and when to call the tool without needing to guess.

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 baseline is 3. The description adds meaningful route-level parameter semantics: which fields to include for native-to-ERC20, ERC20-to-ERC20, and ERC20-to-native swaps, plus worked examples mapping natural-language requests to concrete parameter values. This is genuinely helpful, even though some Args text merely restates schema descriptions.

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 opens with a precise statement of what the tool does: swap one token for another on an EVM network using the user's Monei wallet. The EVM specification in the name and title distinguishes it from the Solana swap sibling, and the three routing combinations clarify the operation beyond a simple tautology.

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 gives explicit pre-call guidance: check balance with monei_get_evm_portfolio, look up contract addresses from the portfolio, and get user confirmation before executing. It also explains exactly how to choose tokenIn/tokenOut fields based on the swap route. It does not explicitly say 'use monei_swap_tokens_solana for Solana', so it stops just short of fully naming alternatives.

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