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

readOnlyHint already covers the safety profile. The description adds useful output-shaping context (results are a history/time series, dates are ISO 8601 UTC, date-only fields use YYYY-MM-DD) which matters because there is no output schema, but it omits currency/units, whether figures are consolidated, and pagination behavior beyond the schema's limit.

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 purpose is front-loaded in the first clause, but the entire date-format section is stated twice in English and Japanese, and the timezone conversion note is verbose for what it conveys. Roughly half the text is duplication rather than new 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?

With no output schema, the description should characterize returned data more fully. It handles date formatting well but says nothing about units, currency, sign conventions, or the shape of free-cash-flow figures, leaving meaningful gaps for a financial-statement tool.

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 symbol, period, and limit are already documented in the schema. The description adds no meaning about parameter interaction (e.g., how limit interacts with period filters), so the baseline 3 applies.

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?

States a specific resource: historical cash flow statements, explicitly including free cash flow. This distinguishes it from get_income_statement and get_balance_sheet, though it does not name or contrast with the closest sibling, get_full_financial_statement.

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?

Usage is only implied by the resource name — an agent can infer this is the tool for cash flow time series, but there is no explicit when-to-use, when-not-to-use, or pointer to an alternative such as get_full_financial_statement for a complete statement set.

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