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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds useful context about the default/max window (already in schema) and importantly explains that zero plays on a new feed is normal due to indexing delays, setting expectations for results. No contradiction 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?

Three concise sentences, each adding value: the core functionality, the use cases, and a caveat about new feeds. No filler, front-loaded with the main purpose.

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?

For a read-only stats tool, the description explains the main output (plays and episodes) and covers an edge case (zero plays). It lacks detail on response format, sorting, or pagination, but given the simplicity and good annotations/schema, it is reasonably 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 documents token and tenant_slug with descriptions, and days has a default/min/max. The description mentions the window defaults but does not add substantive meaning beyond the schema—e.g., it doesn't explain how days affects aggregation or return format. With 67% schema coverage, the description could have compensated more but doesn't.

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 returns plays over a configurable window and the episodes that drive them. It also frames the tool as answering specific questions ('how did last month go', 'which episode is working'). However, it does not explicitly mention how it differs from sibling tools like publisher_episodes or publisher_status.

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 provides clear use cases, such as evaluating monthly performance and episode effectiveness, plus a practical note that zero plays is normal for new feeds. It does not explicitly state when to avoid this tool or suggest alternatives, so it lacks explicit exclusion/alternative guidance.

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