Launch App

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

With no annotations, the description carries the full burden and does a good job: it discloses fuzzy matching, the disambiguation strategy (ranked candidates rather than a guess), and the idempotent foreground check with the force override. It omits failure modes (app not installed / no match) and any permission considerations, which are the notable remaining gaps.

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 short sentences, front-loaded with the primary action and lookup modes before the edge-case behavior. No filler.

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?

An output schema exists, so return values need not be explained. For a launch/mutation-style tool with zero annotations, the description covers matching semantics, disambiguation, and the foreground/force interaction adequately; only the device parameter and error behavior are left unaddressed.

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 0% across 5 parameters, so the description must compensate, and it only partially does: it clarifies that app_name is fuzzy and package_name is exact, and explains force. It says nothing about device, and the schema also exposes an undocumented 'package' parameter that the description never mentions or reconciles with package_name.

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 and resource ('Open an app') and names the two accepted lookup forms (fuzzy app_name vs. exact package_name). It does not distinguish itself from the sibling start_app or lookup_app, so an agent still has to infer which launcher to pick.

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 gives useful conditional behavior (ambiguous names return ranked candidates instead of guessing; already-foreground is a no-op unless force=true), which implicitly tells the agent when the call is safe. However, it never says when to prefer this over start_app, open_deeplink, or open_and_settle, all of which appear to overlap.

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