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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds useful context about what each entry contains, but says nothing about ordering, completeness, caching/staleness of the chain list, or whether the set is static — minor gaps for a reference call with 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?

A single compact sentence with zero waste and the resource front-loaded. The phrasing is a sentence fragment ('Chains Warden supports, with...') that reads slightly awkwardly as a description but delivers the content efficiently.

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?

With no input parameters, no output schema, and a read-only annotation set, the definition supplies enough for correct invocation: it tells the agent the call enumerates supported chains and what fields come back per chain. Only minor detail (ordering or freshness of the list) is absent, which is not essential for calling it.

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 takes zero parameters, so the schema baseline of 4 applies. The description correctly adds no parameter information because there is none to add.

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 names the resource plainly ('Chains Warden supports') and enumerates the attributes returned for each entry (native coin, dollar stable, gasless support). It is immediately distinguishable from swap-oriented siblings like quote_swap or execute_swap, though the verb 'list' is only implied by the title rather than the description.

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?

There is no explicit when-to-use guidance, no statement that this is a prerequisite lookup before quoting or swapping, and no mention of alternatives or exclusions. The agent must infer that this is a discovery/reference call from the content alone.

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