fetch_financials

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

No annotations are provided, so the description carries the full burden. It mentions the API key requirement and return format, which is helpful, but it does not disclose potential errors, rate limits, or whether the operation is read-only. Behavioral transparency is adequate but not comprehensive.

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 well-structured with an Args section and a Returns line. It is concise, each sentence adds value, and there is no fluff. Slightly more conciseness could be achieved, but it is already efficient.

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 presence of an output schema, the description does not need to detail return values. It covers all parameters, the environment variable requirement, and the return type. However, it could be more complete by mentioning error handling or rate limits. Overall, it is sufficient for the tool's complexity.

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 input schema has no descriptions, so the description fully compensates by explaining the format of 'tickers' (comma-separated), enumerating valid values for 'stmt_type' and 'period', and clarifying 'limit' as periods per ticker with a default. This adds substantial meaning beyond the schema.

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 fetches financial statements (income, balance sheet, cashflow) from an API. The verb 'fetch' and resource 'financial statements' are specific, and the tool is distinct from siblings like fetch_prices which fetch price data.

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 specifies a required environment variable but does not explicitly state when to use this tool versus alternatives among the siblings. Usage is implied by the purpose, but there are no exclusion criteria or direct comparisons.

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