get_ema

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

With no annotations provided, the description carries the full burden. It states it uses candle data and returns a time series, but does not describe the output structure, data range, or any edge cases. For a read-only calculation tool, this is minimal but not misleading.

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, well-structured sentence that front-loads the core function (EMA calculation) and includes key parameters. No unnecessary information.

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 4-parameter tool with no output schema, the description gives a high-level overview but does not specify the exact return format (e.g., list of values with timestamps) or the number of data points. It is adequate for a simple indicator but lacks completeness for an agent to fully anticipate the output.

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 baseline is 3. The description mentions 'bar unit, period, and calculation basis' which loosely corresponds to interval, period, and price_field, but adds no additional detail beyond the 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 clearly states that the tool calculates the exponential moving average (EMA) of a stock and returns an EMA time series based on candle data. This specific verb and resource distinguish it from other technical indicator tools like RSI or MACD.

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 the tool is for computing EMA from candle data but does not explicitly mention when to use it over alternatives (e.g., other indicators) or any exclusions. No reference to specific use cases or when not to use it.

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