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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is fully covered by structured data. The description adds nothing on top — no pagination behavior, no default settlement currency, no note that results are a market-data snapshot via openWorldHint.

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 single sentence is front-loaded and wastes no words, but it is concise to the point of under-specification. Brevity here reflects missing content rather than disciplined editing.

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 seven-parameter listing tool with no output schema and a near-identical sibling, the description should at least sketch what a plan record contains and how to disambiguate from the dual-stock variant. Neither is present, leaving the agent reliant entirely on the schema.

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 100%, so all seven parameters (coin, page, sort, type, plan_id, page_size, quote_currency) are already documented in the schema with useful detail such as the sort modes and put/call semantics. The description contributes no additional parameter meaning; baseline 3 applies.

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 "List dual investment plans." is essentially a restatement of the tool name `cex_earn_list_dual_investment_plans`, adding no distinguishing detail. It also fails to separate the tool from the confusable sibling `cex_earn_list_dual_stock_investment_plans`, which an agent could easily pick instead.

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?

No when-to-use, when-not-to-use, or alternative guidance is provided. Given siblings like `cex_earn_list_dual_stock_investment_plans` and `cex_earn_get_dual_stock_project_recommend`, an explicit routing hint was needed and is entirely absent.

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