DCA Statistics

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

The annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is clear. The description adds the return format but does not disclose any additional behavioral traits like data freshness or limits. This adds marginal value beyond annotations.

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 sentence that captures purpose and output structure efficiently. No redundant words or unnecessary details.

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?

Given the output schema exists, the description need not fully explain returns, but it does mention the fields. The tool is simple with one optional parameter, and annotations provide safety guarantees. Minor omission: no mention of data timeframe or update frequency, but overall adequate.

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 schema covers the single parameter with 100% description, but the description adds contextual meaning by stating that omitting the symbol returns stats for all plans. This goes beyond the schema's technical definition.

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 'Get DCA investment statistics' and specifies the exact return structure including fields for both aggregate and per-item data. This distinguishes it from sibling tools like dca_list (list plans) or dca_history (historical actions).

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 implicitly indicates that omitting the symbol returns stats for all plans, but it does not explicitly guide when to use this tool versus alternatives such as dca_list or dca_history. No direct comparison or when-not-to-use advice is provided.

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