compare_assets

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

With no annotations, the description carries the full burden of behavioral disclosure. It clearly states the output (a ticker-by-ticker correlation matrix of daily returns, range -1 to 1) and constrains inputs. It does not describe data sources or error handling, but for a read-only computation tool the core behavior is transparent.

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 concise and well-structured with a one-sentence purpose, an 'Args' block, and a 'Returns' line. Every section earns its place and no redundant fluff is present.

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 tool's simplicity (2 parameters, no output schema, no annotations), the description is complete. An agent can determine required arguments, optional argument values, and the expected result format without any additional context.

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 compensate. It fully documents both parameters: tickers requires 'two or more ticker symbols' with a concrete example, and period lists all allowed values ('1mo','3mo','6mo','1y','2y','5y','10y','ytd','max'). This exceeds what the raw schema provides.

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 opens with a specific verb and resource: 'Compute the correlation matrix of daily returns between two or more assets.' This clearly defines the tool's function and distinguishes it from siblings like get_quote or get_portfolio_metrics, which serve different purposes. The return value is also specified.

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 purpose statement makes the context obvious: use this tool when you need a correlation matrix across multiple tickers. It does not explicitly name alternatives or exclusions, but the sibling tools are distinct enough that no further routing guidance is needed.

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