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

readOnlyHint=true already establishes this as a safe read, so the bar is lower; the description adds that the response includes source and a Vibe Shipped link, which is useful return-content context. It says nothing about auth needs, rate limits, or behavior for a missing/invalid slug.

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?

One sentence, front-loaded with the verb and resource, with the response contents trailing. Nothing is padded or redundant.

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 single-parameter read-only tool with no output schema, the description is adequate but thin: it covers what is returned at a high level yet omits slug provenance, error behavior, and any link to the sibling search tools that produce slugs. No output schema exists, so return-value explanation is legitimately on the description, and it is only partial.

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 single slug parameter has 0% schema description coverage, so the description carries the load and does state that lookup is keyed by slug. It adds no format hints (e.g., slug shape or case sensitivity) beyond the schema's bare 'string' type.

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?

States a specific verb (Get) and resource (one app) with the identifier key (slug), which cleanly separates it from the list-oriented siblings latest_apps and search_apps. It never names those siblings, so the differentiation is inferred from 'one app' rather than stated.

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 when-to-use guidance, no stated prerequisites, and no reference to search_apps as the source of the slug. The only hint is 'by slug', leaving the agent to infer the lookup-after-search workflow.

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