byte_get_token_balances

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

Annotations already declare readOnlyHint, destructiveHint, idempotentHint, and openWorldHint, covering safety. The description adds valuable behavioral context: the network (Arbitrum Sepolia testnet) and the explicit exclusion of Base-mainnet balance, which goes beyond what annotations provide. No contradiction with annotations.

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 two sentences long, front-loading the primary purpose and immediately following with a critical exclusion. Every word serves a purpose, and there is no unnecessary 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?

Given the tool has a single parameter, comprehensive annotations, and an output schema, the description provides sufficient context about the network and the scope of balances. It is complete for the agent to understand usage. A minor improvement could be mentioning the expected balance format, but it's not necessary due to output schema.

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% with a clear description of the address parameter. The tool description does not add additional parameter semantics beyond what the schema provides, so the baseline score of 3 is appropriate.

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?

Description explicitly states the tool gets USDC and ETH balances for an address on Arbitrum Sepolia, clearly identifying the specific tokens and network. It distinguishes itself from the sibling tool byte_buy_data by stating what it does not show (Base-mainnet USDC balance), providing strong differentiation.

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 clearly states when to use this tool (to get specific token balances on a specific testnet) and explicitly excludes when not to use it (for Base-mainnet USDC balance, which is handled by byte_buy_data). This gives the agent clear guidance on tool selection.

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