EVM MCP Server

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

Annotations provide readOnlyHint=false, destructiveHint=true, openWorldHint=true, and idempotentHint=false. The description adds context about using the configured wallet, which clarifies authentication needs beyond annotations. It doesn't mention rate limits or specific destructive consequences, but aligns with annotations without 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?

Two concise sentences with zero waste: first states purpose and scope, second clarifies the wallet mechanism. Front-loaded with essential information, no redundant details.

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?

Given a destructive tool with no output schema, the description is reasonably complete—it covers what the tool does and the wallet context. However, it lacks details on return values (e.g., transaction hash) or error cases, which would be helpful for an agent.

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%, with clear parameter documentation. The description adds no additional parameter semantics beyond what's in the schema (e.g., no examples for 'network' beyond the default). Baseline 3 is appropriate since the schema fully covers parameters.

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 the action ('Transfer native tokens') and resource (ETH, MATIC, etc.), with the specific mechanism 'to an address' and 'Uses the configured wallet.' It distinguishes from sibling tools like transfer_erc20 by specifying native tokens, but doesn't explicitly contrast with other tools beyond that implied difference.

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 for transferring native tokens (vs. ERC20 tokens via transfer_erc20), but doesn't explicitly state when to use this tool versus alternatives like write_contract for more complex transfers or get_balance for checking balances. No exclusions or prerequisites are mentioned.

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