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

No annotations are provided, so the description carries the burden. It explicitly states the HTTP mapping to GET /chains, implying a read-only operation, and specifies what is returned (chain IDs and native gas tokens). It does not mention auth or rate limits, but for a public list endpoint this is acceptable.

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?

Two sentences, no wasted words, and the key information is front-loaded with the API mapping and purpose. Perfectly sized for the tool's simplicity.

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?

Low complexity with no parameters and no output schema. The description sufficiently conveys the tool's purpose and the nature of its response. Minor gap: no mention of response format or whether all chains are always included, but these are not critical for a simple list tool.

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 tool has 0 parameters, so the baseline is 4. The description adds value by explaining the return payload (chains with IDs and gas tokens), which is more than the empty schema alone could provide.

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?

Clearly states it lists supported EVM chains with chain IDs and native gas tokens, using a specific verb and resource. Provides examples (Ethereum, Arbitrum, Base, Polygon, BNB Chain) and distinguishes from sibling tool get_supported_dexes by focusing on chains versus DEXs.

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?

Implies usage when chain information is needed but does not explicitly contrast with alternatives like get_supported_dexes. No explicit when-or-when-not guidance, but the simplicity of the tool makes the intended use reasonably clear.

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