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

With no annotations provided, the description carries the full transparency burden. It discloses non-obvious behavior: default 25-block window, automatic narrowing when a node refuses on result size, and that all caps/narrowings are named in the response. It also mentions the cost ($0.09 via x402) and supported chains. This goes beyond a basic read operation description, though it does not explicitly state read-only semantics or return shape.

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 delivers a lot of information in two sentences without padding. However, it front-loads the cost before the main purpose, and the dense structure mixes cost, function, behavior, and chains into one run-on sentence. It is concise but could be better organized for quick scanning.

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 9 unannotated parameters, no output schema, and no annotations, the description covers the core purpose, defaults, narrowing behavior, response naming, cost, and chains. However, it does not explain the return value structure, x_payment, or provide explicit guidance on parameter combinations (e.g., required address/topic0 is only in the schema, not the description). It is useful but leaves gaps for a complex 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 description coverage is only 33%, so the description must compensate. It adds meaning for the key parameters: 'by contract address and/or indexed topics over a block range' maps to address, topic0-3, and block range. It also explains the default block window. However, it does not clarify x_payment or the exact format/meaning of topic1-3, fromBlock, and toBlock beyond inference.

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 'raw event logs by contract address and/or indexed topics over a block range (eth_getLogs)' and identifies it as 'the indexing primitive.' This is a specific verb+resource that distinguishes it from sibling chain tools by naming the underlying method and its role.

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 as a low-level event log retrieval tool with a default block window and auto-narrowing, but it does not explicitly state when to use it versus other chain query tools or provide exclusion criteria. The phrase 'the indexing primitive' hints at its foundational nature but lacks direct alternative guidance.

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