get_universe_info

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

No annotations are provided, so the description carries the full burden. It discloses that the tool can return an error if the key is analytics-only, and clarifies which parts require different permissions. It does not describe potential side effects (likely read-only) or rate limits, but given the read-only nature implied, this is adequate.

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 fairly concise, covering purpose, data points, use cases, and permission requirements in two paragraphs. It front-loads the core purpose and lists key stats, then adds contextual details. Minor redundancy (like repeating the like ratio mention) but overall efficient.

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 moderate complexity (two params, no nested output schema, no annotations), the description is quite complete. It covers what data is returned, permission nuances, and typical use cases like competitor comparison. The absence of an output schema is compensated by listing the data points explicitly, and the error case is disclosed.

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 already has 100% description coverage for both parameters, so the description doesn't need to reiterate. However, it adds context that universeId can be an alias and optional when a default is set, and includeOpenCloudMetadata controls fetching additional metadata, which aligns with the description's mention of Open Cloud metadata. This slightly exceeds the baseline.

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 fetches metadata and public storefront stats for an experience, listing specific data points like name, description, creator, dates, player count, visits, and like/dislike ratio. It also explicitly contrasts with the Analytics Query API, distinguishing it from sibling metric tools.

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: public stats need no API key and work for unowned experiences (useful for competitor comparison), while Open Cloud metadata requires a key with universe read access. It also indicates when to use this tool over others (e.g., complements metric tools for retention analysis) and mentions alternatives like find_universes for ID lookup.

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