Download System Apk Variant

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

With no annotations present, the description carries the full burden. It clearly states the core behavior—downloading bytes to a local file—and implies no server-side mutation. However, it does not disclose local overwrite behavior, authorization requirements, or explicitly state that the operation is read-only with respect to the system APK variant.

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 with no filler. The core operation, object, and destination are front-loaded, and every word contributes to the meaning.

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 simple download operation, the description plus a fully documented schema and an output schema is largely sufficient. The main gap is lack of alternative-routing guidance, but that is already penalized under usage_guidelines and does not make the tool call ambiguous.

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%, and each parameter already has a meaningful description, including variant_id's source from list_system_apk_variants. The tool description adds no parameter-level detail beyond what the schema provides, so the baseline of 3 is appropriate.

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 ('Download'), a specific resource ('previously created system APK variant'), and the destination ('to a local file'). This clearly distinguishes it from create/get/list variants and from download_generated_apk by the system-variant qualifier.

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 phrase 'previously created' implies this should be used only after a variant exists, which is a usage condition. However, there is no explicit guidance about when to choose this over alternatives such as list_system_apk_variants or download_generated_apk, or what to do when the variant ID is unknown.

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