ratio_analysis

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

Annotations already indicate readOnly and idempotent, and the description adds 'deterministic' and 'Pure calculation', reinforcing the absence of side effects. It does not describe error handling or output specifics, but with annotations covering the core behavioral traits, the addition is sufficient.

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, using two sentences that front-load the core purpose and then clarify the calculation nature. No unnecessary words or redundancy, making it easy to parse quickly.

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 description does not specify the output format or the exact ratios computed, which could be useful for an agent deciding whether this tool meets a need. However, given the tool name and the mention of 'profitability, liquidity, leverage, returns', the intent is reasonably clear, though a brief output summary would improve completeness.

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 statements parameter is well described with 'Chronologically ordered (oldest first) financial statements, e.g. from the financial_statements tool', which adds important context about ordering and source. The optional companyName lacks a description, but it is self-explanatory and not required, so the coverage is adequate.

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 the tool performs deterministic financial ratio analysis and multi-period CAGR trends, with a specific verb and resource. It distinguishes itself from siblings by explicitly noting it is a pure calculation tool, not a search or generation tool.

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 when to use it: when you already have financial statements and need ratio analysis, as evidenced by 'over a set of FinancialStatement objects' and 'Pure calculation — no search'. It does not name alternatives explicitly, but the contrast with search tools is clear enough.

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