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

Adds real context beyond annotations: the 100-log result cap, the 1,000-block retention window, and the $0.001 USDC x402 payment per successful call, which explains why readOnlyHint is false for a query-shaped tool. It stops short of stating whether truncated results can be paged or completed, so it is strong but not exhaustive.

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?

Four tight sentences, front-loaded with the core behavior and scope, then the return shape, then the use case, then the cost. Nothing is redundant and every sentence carries information an agent needs.

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?

With no output schema, the description covers the return payload (up to 100 logs with block, tx hash and topics), the scan window, the filter, and the payment cost — enough to call the tool correctly. It omits how to retrieve results beyond the 100-log cap, which is the only notable gap.

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 100%, so the schema already documents blocks (1-1000, default 50), topic0 (0x event signature hash) and address. The description largely restates these (the 1,000 cap, topic0 as 'event signature hash') and adds only the implicit constraint that address is a contract, so the baseline 3 applies.

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?

States a specific verb and resource ('recent event logs emitted by a contract'), names the chain (Base), the lookback scope (last N blocks, up to 1,000) and the optional filter (topic0). An agent can distinguish this from the sibling log tools (eth_logs, arb_logs, polygon_logs, op_logs) purely from the description.

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?

Gives a positive use case ('Use to watch transfers or contract events') but no when-not guidance and no routing to alternatives such as eth_logs for other chains or base_receipt for a single transaction. Usage is implied rather than explicitly bounded.

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