Block MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool checks balances 'across multiple blockchains,' which implies it might aggregate data from different sources, but doesn't detail how this works (e.g., rate limits, error handling, or what 'native token' means specifically). For a tool with no annotation coverage, this leaves significant gaps in understanding its behavior and constraints.

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 appropriately sized and front-loaded, with the core purpose stated first and parameter details following in a clear 'Args:' section. There's no wasted text, though the structure could be slightly more integrated (e.g., merging the address note into the main sentence).

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 an output schema (which likely defines return values), the description doesn't need to explain outputs. However, with no annotations and low schema coverage, it should do more to cover behavioral aspects like error cases or blockchain specifics. The description is adequate for a simple query tool but lacks depth for full contextual understanding.

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 description adds meaningful context for the single parameter 'address' by specifying it 'must start with 0x,' which clarifies format requirements not evident from the schema (which has 0% description coverage). This compensates well for the low schema coverage, though it doesn't explain potential variations or validation details beyond the prefix.

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: checking native token balances across multiple blockchains. It specifies the verb ('check') and resource ('native token balance of a wallet'), making it easy to understand. However, it doesn't explicitly differentiate from sibling tools like 'get_transactions' which might also involve wallet data, so it doesn't reach the highest score.

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 no guidance on when to use this tool versus alternatives. It doesn't mention sibling tools like 'get_transactions' (which might provide transaction history) or 'convert_crypto' (which might involve balances), nor does it specify prerequisites or exclusions. The only usage hint is the address format requirement, which is minimal guidance.

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