getHistoricalStockGrades

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

Annotations already declare readOnlyHint=true and idempotentHint=true. The description adds value by specifying 'historical changes in analyst ratings', indicating the data is a time series of rating changes. This provides context beyond what annotations alone convey. However, it omits details on data freshness, pagination, or rate limits.

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 two sentences long, front-loading the purpose. Every sentence contributes meaning. 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?

With no output schema, the description could have explained what the tool returns (e.g., list of grades with dates, analyst names). It only says 'comprehensive record' and 'track historical changes'. Input schema is simple. Annotations are strong, but the lack of output description leaves ambiguity about the return structure.

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 achieves 100% description coverage for both parameters (symbol and limit). The description does not add any additional parameter-specific meaning beyond what the schema provides. 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 accesses a 'comprehensive record of analyst grades' and allows tracking 'historical changes in analyst ratings for specific stock symbols'. This clearly identifies the resource (historical grades) and action, distinguishing it from sibling tools like getStockGrades (likely current) and getStockGradeSummary.

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 data ('track historical changes') but does not explicitly state when to use this tool over alternatives like getStockGrades or getRatingsSnapshot. No exclusions or when-not-to-use guidance is provided. With many sibling tools, better guidance would improve this score.

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