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

Annotations already provide safety and idempotency hints. The description adds value by specifying the supported chains (Ethereum, Optimism, etc.) and the exact data returned (balance, tx count, token stats). It does not contradict any annotations.

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 fairly long due to listing many chain names and example queries. While it starts with useful examples, the extensive list could be shortened or summarized. It earns its place but could be more concise.

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?

The tool has only two parameters and an output schema exists (implied). The description covers purpose, parameters, and return types. It does not mention limitations like rate limits, but for a simple read-only tool, this is adequate.

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 the description reinforces that 'chain' is a slug (referencing list_chains) and 'address' is a 0x address. It provides concrete examples of valid chain values and addresses, adding helpful context beyond the schema's brief description.

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 an on-chain address summary across 20+ EVM chains, including balance, transaction count, and token-holding stats. It provides example queries that illustrate the purpose, and distinguishes it from sibling tools like get_address_token_transfers and get_address_txns by focusing on a summary rather than specific transfers or transactions.

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 explicitly instructs to pass a chain slug and 0x address, and gives examples of when to use the tool (e.g., 'What's the balance of [wallet]'). It implicitly differentiates from siblings by listing the returned data, but does not explicitly state when not to use it or name alternatives.

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