Compare Symbols

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

The annotations already state readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the agent knows it's a safe read. The description adds the specific metrics computed, but does not disclose data sources, calculation methods, or limitations. With annotations covering safety, this meets baseline but adds only marginal behavioral context.

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 with no filler words. The description is front-loaded with the action and immediately lists the three comparison aspects, making it easy to parse.

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 simple comparison tool, the description names the three output areas, which gives a clear expectation of what the result will contain. However, without an output schema, it does not detail the exact return structure or how period_bars affects results, so it is not fully complete. Given the simplicity, a 4 is appropriate.

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 coverage is 100% with descriptive parameter definitions (symbol1, symbol2, period_bars). The description adds no parameter-specific semantics beyond what the schema already provides; it focuses on output dimensions. Thus baseline 3 is appropriate.

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 uses the specific verb 'Compares' and names three concrete comparison dimensions (relative strength, price correlation, return performance) against two tickers. This clearly distinguishes it from sibling tools that fetch data or analyze single symbols.

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 should be used when an agent needs to compare two tickers' performance and correlation, but it does not explicitly state when to prefer this over alternatives like get_market_analysis or scan_watchlist. No exclusionary guidance is provided.

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