List RevenueCat Chart Metrics

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint false. The description adds value by specifying the return format (Markdown-formatted list grouped by category), how metric names should be used in rc_get_chart, and providing example queries. No contradictions with annotations.

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 well-structured with Args, Returns, and Examples sections. Every sentence adds value; no fluff or redundancy. It is appropriately sized for a simple single-parameter tool.

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 optional parameter with enum, no output schema), the description is complete. It explains the return format, purpose, and relationship to sibling rc_get_chart, fully enabling correct use.

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%, so baseline is 3. The description goes beyond by listing the exact category enum values in the Args section and giving concrete examples with natural-language queries, which clarifies how to use the parameter.

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 lists all available RevenueCat Charts API metrics with descriptions, using a specific verb ('List') and resource ('RevenueCat Charts API metrics'). It distinguishes from sibling rc_get_chart by noting it's for discovery before calling rc_get_chart.

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?

Provides explicit guidance on when to use ('Use this to discover what subscription data you can query before calling rc_get_chart') and names the alternative rc_get_chart. It lacks an explicit 'when not to use' statement but implies it through the 'before calling' context.

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