Binance.US MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It effectively describes the tool's behavior by specifying the API key requirement (⚠️ REQUIRES CUSTODIAL SOLUTION API KEY) and detailing the return structure with two lists and their contents. This covers key operational aspects beyond basic functionality.

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 well-structured and front-loaded with the core purpose, followed by important warnings and return details. Every sentence adds value: the first states the purpose, the second highlights requirements, and the subsequent lines explain the output structure efficiently without redundancy.

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 tool with no annotations and no output schema, the description does a good job of covering essential context: it explains the purpose, requirements, and return format. However, it could be more complete by mentioning potential errors, rate limits, or authentication details beyond the API key note, given the complexity of custodial operations.

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 input schema has 100% description coverage, clearly documenting the single required parameter 'rail' as a custodial partner identifier. The description doesn't add any parameter-specific information beyond what the schema provides, so it meets the baseline of 3 without compensating for gaps.

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's purpose with specific verbs ('Get list of assets') and resources ('supported for custodial transfers and settlements'). It distinguishes from sibling tools like 'binance_us_cust_supported_assets' by specifying the custodial context, making the scope unambiguous.

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 provides clear context for when to use this tool (for custodial transfers/settlements) and includes a warning about API key requirements. However, it doesn't explicitly state when NOT to use it or name specific alternatives among the many sibling tools, such as 'binance_us_cust_supported_assets' for non-custodial contexts.

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