eth-block

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 mentions return fields, supported chains, and cost, but it does not disclose whether the operation is read-only, any authentication or rate-limit requirements, side effects, or limits (e.g., maximum block range). For a tool with no annotations, this is insufficiently transparent.

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 extremely concise: two sentences with no wasted words. The first sentence presents the core purpose and input types, and the second covers fields, chains, and cost. Every sentence adds value, and the most critical information 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?

Given that the tool has only two optional parameters and no output schema, the description provides the essential information: what it returns, which chains it supports, and the cost. However, it fails to explain the behavior of specific tags like 'safe' or 'finalized,' and does not mention any constraints or error handling. It is adequate but not fully complete for a simple lookup tool.

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%, and both parameters have schema descriptions. The tool description does not add new meaning beyond what the schema already provides for the 'number' and 'network' parameters. However, the description lists the fields returned, which indirectly helps understand the tool's output. Since the schema already explains the parameters, a 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?

The description clearly states what the tool does: 'Returns an Ethereum block header and transaction hashes by block number, hex string, or tag.' It specifies the action (Returns), resource (Ethereum block header and transaction hashes), and input types. It also lists the fields returned and supported chains. However, it does not explicitly differentiate from a sibling tool like 'block-intel,' which may have similar functionality.

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 explains when to use the tool (to get block header and transaction hashes) and the input formats (number, hex, or tags). It provides context for valid tags but does not mention when not to use it or suggest alternatives among the many sibling tools. It gives a clear context of use but lacks exclusions or guidance on choosing this over similar tools.

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