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

With no annotations, the description carries the full burden. It usefully discloses that the call is free, scoped to Base, and performs format plus EOA/contract detection, but says nothing about failure behavior for malformed addresses, latency, or what the response looks like, which matters since there is no output schema.

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?

One sentence, front-loaded with the 'Free:' qualifier and the scope, with zero filler. Slightly dense and could separate the chain scope from the cost note, but nothing is wasted.

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?

For a single-parameter validation tool with no output schema, the description covers the essentials: cost, chain, and the two things checked. It falls short only on return-value shape and invalid-input behavior.

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 0%, so the description must compensate for the single 'address' parameter. It adds real meaning by specifying a 0x-format address on Base, but says nothing about whether the 0x prefix is required, case sensitivity, or checksum handling.

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 states a specific verb and resource: it checks the 0x address format and whether the address is an EOA or contract on Base. That is far more specific than the title 'Validate an address,' and 'before you pay' implicitly separates it from the paid approvals_quote sibling.

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?

'before you pay' conveys sequencing relative to the paid quote tool, so the intended usage is implied rather than stated. There is no explicit 'use this when...' statement or exclusion, leaving the agent to infer that this is the pre-flight step for approvals_quote.

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