stock_historical

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

No annotations are provided, so the description bears the burden. It discloses that it returns OHLCV data with summary stats, which is useful. However, it does not mention potential caveats like rate limits, data availability for certain exchanges, or that intraday intervals may be limited by period (e.g., 1m data only available for recent periods). This is a moderate disclosure, neither rich nor misleading.

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 and well-structured: a one-sentence purpose, a return type line, Args with enumerated options, and two clear examples. Every sentence earns its place with no 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?

With an output schema present, the return format doesn't need explanation. The description covers purpose, parameters, and examples. It lacks explicit notes on parameter constraints (e.g., 1m interval only for short periods), but for a straightforward historical data tool it is adequately complete.

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 0% description coverage, meaning parameter descriptions are absent. The tool description compensates by explicitly listing valid period and interval values, and providing examples that map symbols to real companies. This gives the agent essential semantic context beyond raw schema, though it doesn't detail output format.

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 'Get historical price data for any global stock' with a specific verb and resource. It distinguishes itself from siblings like stock_quote (current price) and crypto_historical (crypto-specific) by specifying 'global stock'. The Args and Examples further clarify what the tool does.

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 usage for historical price data retrieval, with examples showing typical calls. However, it doesn't explicitly contrast with alternatives like stock_quote for current prices or technical_indicators for derived metrics. The context is clear enough for an agent to select this tool when historical OHLCV data is needed.

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