index_pe_history

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

No annotations are provided, so the description must convey behavior. It only adds a date format note (YYYY-MM-DD). It does not disclose whether data is daily, how far back history goes, whether index names require a specific format, or what the return structure looks like. This is minimal behavioral transparency.

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 a single concise sentence with a date format note, front-loading the key action and resource. Every word earns its place; no redundancy or fluff.

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 historical data tool, the description covers core purpose and date format, but lacks information about accepted name values, data frequency, and response structure. Without annotations or output schema, it leaves gaps, though the tool's simplicity mitigates this somewhat.

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 schema lists three parameters (name, from_date, to_date) with no descriptions. The description clarifies date format but provides no guidance on what 'name' should contain (e.g., index symbol, full name) or whether dates are inclusive. With 0% schema coverage, this insufficiently compensates.

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 identifies the tool's function: retrieving historical valuation metrics (P/E, P/B, dividend yield) for an index. This distinguishes it from siblings like index_history, which likely provides price history. The specific metrics make the purpose unambiguous.

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 the tool should be used when historical valuation ratios for an index are needed, but it does not explicitly state when to prefer this over index_history or stock_history, nor does it mention any exclusions or prerequisites. Guidance is implied rather than explicit.

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