evm_erc20_balanceERC20 token balance for any wallet - USDC, USDT, DAI or any token - via balanceOf. Returns the raw amount and the decimals so you can format it. Flat $0.001 per call, paid over x402 (USDC).
| Name | Required | Description | Default |
|---|---|---|---|
| chain | No | base | ethereum | polygon | arbitrum | optimism. | |
| token | Yes | ERC20 contract address. | |
| address | Yes | Wallet to look up. |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden of revealing behavior. It states the call reads balanceOf, returns raw amount plus decimals, and includes pricing/payment details. It does not mention failure modes or chain handling, but the core read-only behavior and cost are disclosed.
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 compact and directly informative, with no redundant wording. It conveys purpose, return content, and pricing in two short sentences.
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 there is no output schema, the description usefully explains that the response contains the raw amount and decimals for formatting. It also includes cost/payment context. It does not give an exact response shape or error behavior, but the essential call context is present.
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?
All three parameters are documented in the schema with clear semantics: chain lists supported values, token is the ERC20 contract address, and address is the wallet. Since schema coverage is 100%, the description adds little beyond the schema, though it does not clarify the optional nature of the chain parameter.
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 an ERC20 token balance for a wallet, naming specific tokens and the balanceOf mechanism. It is easily distinguished from sibling tools like evm_balance (native balance) and evm_erc20_allowance.
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 describes when to use the tool: to get an ERC20 token balance for any wallet/token. It does not explicitly contrast with native balance or other ERC20-related tools, but the purpose is specific enough that an agent can infer appropriate usage.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.