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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the agent knows this is a safe, closed-domain read. The description adds useful framing with "Sourced facts," implying curated/authoritative content, but says nothing about volume, freshness, or how the facts are returned.

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?

A single sentence that front-loads the resource domain and ends with the audience cue. No filler, no repetition of the title or annotations.

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 zero-param read tool the description is serviceable, but with no output schema it never indicates the form or scope of the returned facts (a list? prose? per-topic sections?), leaving the agent to guess at the response shape.

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 tool takes zero parameters, so there is no parameter semantics for the description to compensate for. The baseline for a parameterless tool is a 4.

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 names a specific resource domain (App Store billing retry, grace periods, win-back offers, Retention Messaging) with a stated audience, so an agent knows exactly what content this tool surfaces. It does not, however, differentiate itself from siblings like get_winback_overview or get_winback_pricing, which sit in the same topical neighborhood.

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?

"For founders planning a win-back" implies a usage context but stops short of stating when to call this versus get_winback_overview or get_winback_pricing, and offers no exclusions. Usage must be inferred from the topic overlap with siblings.

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