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

Annotations already mark it read-only, idempotent, and non-destructive. The description adds genuinely useful behavior beyond the annotations: it is pure checksum/format validation with no network calls, detects several chain types, and distinguishes Solana wallets from PDAs. This gives agents a clear safety and behavior profile.

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 core purpose is front-loaded in the opening question and the chain list is compact. The benefit phrases ('catches the typo...', 'price: free') are slightly promotional but not bloated; every sentence adds some orienting information.

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, read-only validator, the description covers what it validates, which chains it supports, and that it makes no network calls. It doesn't specify the exact return shape (e.g., boolean plus chain name), but the stated question 'and for which chain?' strongly implies the output. Given the low complexity, this is nearly complete.

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?

The schema only says 'address' is a required string with no description (0% coverage). The description compensates by explaining that the address may be an EVM, Solana, Bitcoin, Tron, or Cosmos-style address and that validation is format-only. It doesn't give examples or formatting details, but for a single obvious string parameter this is adequate.

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 clear purpose: validate an address and identify its chain, listing EVM, Solana, Bitcoin, Tron, and Cosmos formats. It distinguishes itself from chain-specific siblings by advertising 'any chain', though it never explicitly names an alternative such as evm_address.

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 when to use it—when you need offline format/checksum validation across multiple chains—and says 'no network calls'. However, it gives no explicit when-not-to-use guidance or named alternative for chain-specific or network-dependent checks.

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