get_eth_balance

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

With no annotations, the description carries the full burden. It discloses the tool's read-only nature implicitly and explains the purpose (gas fees), but does not detail side effects, authorization needs, or return format, though for a simple balance check these are minor omissions.

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 extremely concise at two sentences, front-loads the core purpose, and contains no filler or redundant information.

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 simple balance check tool with good parameter coverage and no output schema, the description is adequate, though it could optionally mention the output format (e.g., in wei or ether) for completeness.

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?

The schema already describes the 'wallet' parameter as 'Ethereum address to check', but the description adds meaning by specifying the network (Arbitrum) and the relevance (gas fees), adding value beyond the schema.

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 verb ('Get'), the resource ('ETH balance of a wallet'), and the network ('on Arbitrum'), effectively distinguishing it from sibling tools that get other token balances or vault status.

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 provides clear context when to use this tool (to check ETH balance for gas fees), but does not explicitly mention when not to use it or compare to alternatives beyond implicit differentiation from sibling names.

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