get_coverage_index

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

No annotations are provided, so the description bears the full burden. It mentions the formula components and the signal interpretation, but does not disclose whether this is a read-only operation, any limitations (e.g., data availability, rate limits), or that it is a Pro-tier feature. The description is too brief to cover behavioral traits.

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, using sentence fragments to convey the core idea and formula. It is front-loaded and avoids superfluous text. However, it could be restructured to be more understandable (e.g., starting with a clear verb) without becoming lengthy.

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 tool has no output schema and the description does not explain what the return value contains (e.g., numeric value, metadata). Given the complexity of the index and many sibling tools, the description should provide more context about the output format, units, or example usage to be 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 schema has 100% coverage with descriptions for both parameters ('Rolling window.' and 'Entity slug.'). The description in the tool adds no additional semantics beyond the schema, so the baseline score 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 defines the tool as a 'BCA Coverage Index' with a formula and states that high values signal accumulation before price. This gives a clear sense of what it computes and its interpretation, distinguishing it from sibling tools like 'get_fear_greed' or 'get_sentiment'. However, it lacks a direct verb+resource statement (e.g., 'Retrieve the coverage index').

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 guidance on when to use this tool versus alternatives. The description mentions 'Pro tier' but does not explain when it is appropriate to call this tool compared to similar coverage or sentiment tools in the sibling list. There are no examples or exclusion criteria.

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