is_device_secure

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

With no annotations provided, the description carries the full burden. It discloses that the tool reports a boolean state and frames it as a verification step, adding context beyond a bare API name. It does not mention side effects (likely none), but for a simple read-only query, this level of transparency is sufficient.

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?

Two sentences: the first states the core function and API, the second gives a concrete use case. Every word earns its place, and the front-loaded structure makes the tool's purpose immediately clear.

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 query tool with one optional parameter, the description fully covers what the tool does, when to use it, and its relationship to set_device_lock. No output schema exists, but 'Report whether' already conveys the return type. The context is complete for an agent to select and invoke it correctly.

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 has 100% description coverage for the single optional 'serial' parameter, so the schema already documents its meaning. The description adds no additional parameter semantics, which is acceptable since schema coverage is high.

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 uses a specific verb ('Report') and resource ('secure lock screen'), and specifies the underlying API (KeyguardManager.isDeviceSecure). It clearly distinguishes from sibling tools like has_biometric_enrolled by focusing on lock-screen security rather than biometrics.

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?

It explicitly says 'Use it to verify set_device_lock worked before running a Keystore-gated flow,' providing a clear when-to-use scenario. It does not explicitly mention when not to use or list alternatives, but the directive is unambiguous for common cases.

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