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

Annotations already declare readOnly/destructive/idempotent/openWorld, and the description still adds genuinely non-structured behavior: pay-per-call pricing ($0.01 via x402 USDC or card key, first 25 free, failed calls free), that repeats are billed and therefore not free, and the return size cap (up to 100 logs). That is exactly the kind of cost/limit context the annotations cannot express.

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?

Front-loaded with method and scope, then guidelines, example, and pricing in a sensible order. Slightly overloaded at the end: 'Reads or computes only and changes nothing' largely restates readOnlyHint/destructiveHint, and the billing terms earn their place but add bulk.

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?

There is no output schema, and the description covers the return shape (up to 100 logs with block, transaction hash, topics), the scanning window, and cost per call. An agent has everything needed to decide to call it and to interpret the result.

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%, so the baseline is 3. The description still adds value: it clarifies topic0 is a 0x 32-byte event signature hash (useful for knowing to pair with keccak), restates the blocks default/range inline, and supplies a concrete address example.

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?

Names the exact RPC method (eth_getLogs), the resource (contract event logs), the chain (Base), and the scope (last N blocks). It is immediately distinguishable from base_receipt and from the other chain-prefixed log tools by the explicit 'Base' prefix and event-log framing.

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 ('watch transfers or contract events') and an explicit exclusion routing to a sibling ('for one transaction's outcome use base_receipt'). No guidance on when to prefer base_token_transfers or the equivalent logs tools on other chains, but the core when/when-not pair is present.

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