market_get_fear_greed_historical

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 states the scope (historical data over N days) and implies a read-only operation, but it does not disclose the response structure, whether pagination is involved, or any limitations beyond the parameter bounds. For a simple getter, the basic behavior is clear, but additional details would be beneficial.

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 sentence that is direct and front-loaded with the verb. It contains no fluff or redundant information, making it highly concise and easy to parse.

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 tool's simplicity (one parameter, no output schema), the description is somewhat minimal. It explains what it fetches and the parameter, but does not mention the format of the returned data (e.g., array of date/value pairs), which would be helpful for an agent to know how to use the result. It is adequate but not rich, so a 3 is warranted.

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?

Schema description coverage is 100% for the single 'days' parameter, which already includes min/max and a description. The phrase 'for specified number of days' adds no extra meaning beyond the schema, so the baseline of 3 is appropriate.

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 retrieves historical Fear & Greed Index data for a specified number of days. The verb 'Get' and resource 'historical Fear & Greed Index data' are specific, and the distinction from siblings like market_get_fear_greed_current is implicit and clear.

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: when historical data over a day range is needed. However, it does not explicitly mention alternatives (e.g., market_get_fear_greed_current for current value, market_analyze_fear_greed_trend for analysis) or provide conditions for when to choose this tool over siblings. The guidance is present but only implied.

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