futures_spot_price_previous

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

Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description adds that the return is a pandas DataFrame with spot prices and basis, and provides a source URL. It does not disclose edge cases like invalid dates or non-trading days, but this is a simple read operation.

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 compact and front-loaded with the main purpose. The URL and docstring-style params/returns are organized, though the type information duplicates what the schema provides. Overall, it is appropriately concise.

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?

The lack of output schema and minimal description leave several gaps: exact date format, handling of non-trading days, and differentiation from similarly named tools. The name 'previous' conflicts with the description's 'specific trading day', and without more detail, an agent may not correctly invoke this tool.

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?

With 0% schema description coverage, the description must compensate. It states the date parameter is a trading day/historical date and its type, but it does not specify the expected date format. The URL example uses YYYY-MM-DD while the schema default is YYYYMMDD, creating ambiguity that can lead to incorrect 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 it retrieves spot prices and corresponding basis for a specific trading day, using a specific verb and resource. However, it does not differentiate from sibling tools like futures_spot_price_daily or futures_spot_price, and the name 'previous' may imply a specific day while the description says any trading day.

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 explicit when-to-use or when-not-to-use guidance is provided. The mention of '历史日期' implies historical usage, but there are no alternatives named and no exclusions, leaving the agent to guess among many futures spot tools.

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