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 covered. The description adds useful sourcing context ('DefiLlama-sourced', 'via WanBridge'), but does not disclose return format, pagination, or whether the data is live vs cached; this is acceptable given the simple read-only role.

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?

One sentence delivers the core scope and data provenance without redundancy. The most important qualifier (Wanchain-native vs cross-chain) comes first, and the parenthetical is compact and informative.

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 tool with one optional parameter, no required arguments, and a read-only annotation, the description is nearly sufficient for an agent to select and invoke it. It lacks explicit return-value details, but given the absence of an output schema and the simplicity of the tool, the description covers the essential selection and invocation context.

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 description coverage is 0%, but the single optional section parameter has self-documenting enum values wanchain/crosschain/all. The description indirectly maps to these values through 'Wanchain-native' and 'cross-chain', yet it never explains the default behavior or the meaning of 'all', leaving the description to provide only partial compensation.

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 identifies the resource: Wanchain-native earn positions and cross-chain yield opportunities sourced from DefiLlama via WanBridge, which separates it from the address/transaction/bridge sibling tools. It lacks an explicit verb like 'lists' or 'returns', but the tool name supplies the get action and the scope is unambiguous.

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 use for yield-related queries by naming the resource, but it never explicitly tells the agent when to prefer this tool over siblings or how the section parameter should be set for particular intents. No exclusions or alternative routing are provided, so guidance is only implicit.

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