get_historical_data

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

With no annotations available, the description carries the full burden of behavioral disclosure. It only says 'Fetch historical stock data' which implies a read operation, but doesn't state any limitations, the nature of the returned data (e.g., OHLCV), or whether any rate limits or permissions apply. There is no explicit statement that it is read-only.

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 exceptionally concise: a single lead sentence plus a straightforward parameter list. Every sentence earns its place, and the structure front-loads the core purpose before detailing arguments. No filler or redundancy.

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?

For a simple two-parameter tool with no output schema, the description adequately explains the main purpose and all parameters. However, it lacks any mention of what the returned data looks like, any usage constraints, or relationship to sibling tools. Given the minimal complexity, it is borderline adequate but leaves room for more helpful 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?

The description adds meaningful context beyond the schema by explaining 'symbol' as 'Stock ticker symbol' and 'period' with concrete examples of valid values ('1d, 5d, 1mo, 3mo, 1y'). Since the schema has no descriptions for properties, this fills a critical gap and helps the agent construct valid calls.

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 historical stock data, which is a specific verb and resource. It distinguishes from siblings like get_stock_price (current price) and get_company_info by the 'historical' qualifier, though it doesn't explicitly name alternatives.

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?

No guidance is provided on when to use this tool versus alternatives such as get_stock_price for current quotes or get_market_indices for broader market data. The description only states what it does, not when it should be preferred.

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