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

Annotations already declare readOnlyHint=true, openWorldHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds that it returns live prices and is chain-specific, which is useful context beyond annotations. However, it doesn't mention potential limitations, rate limits, or error behaviors, so it doesn't go beyond the baseline for annotated tools.

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 a single concise sentence that states the core purpose and scope, followed by a concrete example. No filler or redundant information, and the key point is front-loaded.

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 read-only tool with three simple parameters, no output schema, and annotations covering safety, the description adequately explains what the tool does and how to invoke it with an example. The only missing element is an explicit description of the return format, but that is not critical given the clarity of the purpose.

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 all three parameters (chain, _apiKey, address) documented in the schema. The description adds an example that maps parameters to actual values, which is helpful but doesn't add semantic detail beyond the schema. Baseline 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?

The description clearly states the tool returns ERC20 token balances with live USD prices for a wallet on a given chain, using a specific verb ('returns') and resource ('ERC20 token balances'). While it doesn't explicitly name sibling tools, the scope is distinct enough from moralis_wallet_history or moralis_wallet_net_worth that an agent can infer its purpose.

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 via an example and the phrase 'for a wallet address on a given EVM chain', but it doesn't explicitly state when to use this tool versus alternatives like moralis_wallet_net_worth or moralis_token_holders. There are no exclusions or conditions, so the guidance is implied rather than stated.

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