get_income_statement

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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds only the return shape and period semantics; it says nothing about auth requirements, rate limits, or error behavior, which is a modest addition over structured data.

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?

Front-loads the purpose in one sentence, then the two parameters and the return summary in a compact Args/Returns layout. Slightly boilerplate in form but no sentence is wasted.

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?

An output schema exists so return fields needn't be spelled out, and the single required parameter is documented. What is missing is the usage context — when this statement is preferred over ttm_financials or the financial summary — which the description leaves to the agent.

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 0% and the period parameter has no enum in the schema, so the description carries the full burden — and it does so by enumerating 'annual', 'quarterly', 'ttm' and explaining ttm as trailing twelve months, plus clarifying ticker is a stock ticker symbol. Only a minor gap: the default of 'annual' is not restated.

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 verb and resource ('Get income statement data') and the returned content (revenue, expenses, net income), which the agent can distinguish from siblings like get_balance_sheet and get_cash_flow. It never explicitly names those siblings as alternatives, so differentiation is inferential rather than stated.

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?

There is no when-to-use guidance, no prerequisites (e.g., ticker must be valid), and no routing against near-neighbors such as get_ttm_financials or get_financial_summary. Usage must be inferred entirely from the name and the period values.

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