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

No annotations are provided, so the description carries the full burden. It notes 'Maps to GET /chains' (implying HTTP method), but does not explicitly state that the tool is read-only, idempotent, or free of side effects. The behavioral transparency is adequate but not rich.

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 a single, front-loaded sentence that efficiently conveys the HTTP mapping, purpose, and output details. Every word earns its place with no redundancy.

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, yet the description only lists example chains and mentions 'chain IDs and native gas tokens' without specifying the exact structure (e.g., array of objects, field names). While adequate for a simple listing, additional structure detail would improve completeness.

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 zero parameters, so schema coverage is 100%. The description adds value by clarifying the output content (chain IDs, native gas tokens, examples), which goes beyond the empty schema.

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 explicitly states the tool lists supported EVM chains with chain IDs and native gas tokens, and provides concrete examples (Ethereum, Arbitrum, Base, Polygon, BNB Chain). This clearly differentiates it from sibling tools like analyze_pool or get_swap_quote.

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 does not provide explicit guidance on when to use this tool versus alternatives. However, given its zero parameters and simple listing purpose, the usage context is implied; there is no exclusionary or alternative tool mentioned.

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