指数移动平均

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

Annotations already declare readOnlyHint=true, so the tool's non-destructive nature is known. The description adds context by revealing that the tool pulls K-lines internally and uses the first price as the smoothing seed, but it does not specify behavior for insufficient data or limit/period pitfalls. No contradiction exists.

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?

It is a single front-loaded sentence that introduces the main action before modifiers, and adds only concise formula-relevant detail. The term "直连版" is a slight ambiguity that could be clearer, so it is not a perfect score.

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?

The output schema and read-only annotation covered return structure and safety, and the description covers the core algorithm. However, with four poorly specified parameters, no sibling differentiation, and no usage alternatives, the definition does not fully equip an agent to choose and calibrate the call across similar indicators.

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%, so the description must supply parameter meaning. It only elaborates on period, calling it the周期, and gives the smoothing-seed behavior; it does not explain limit, interval usage, or how symbol/interval parameterize the K-line pull. This leaves much of the parameter understanding to inference.

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 states a clear operation and resource: "拉取 K 线后计算指数移动平均" and returns an "EMA 序列". It also gives a useful formula detail (first price as smoothing seed). It does not explicitly contrast with sibling tools like indicator_sma or indicator_macd, which prevents a 5.

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 provides no when-to-use direction, no stated preference compared to other indicator tools, and no examples of scenarios where EMA is appropriate. The only contextual phrase "直连版" is ambiguous and does not explain selection between this and sibling indicators.

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