System Intent

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

No annotations are provided, so the description carries the full behavioral burden. It does disclose the prefill-only behavior for dial and compose_sms, but it does not mention side effects, permission requirements, confirmations, or the role of the 'skip_ui' parameter (default true). For a tool that can create alarms, timers, calendar events, and navigate, this is a significant transparency gap.

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 compact and information-dense, using a function-signature style to pack multiple verbs, parameter lists, formats, and one behavioral caveat into a few lines. Every sentence contributes value, and the core purpose is front-loaded.

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?

The description covers the main verb-specific parameter mappings and some formats, which is good for such a multi-action tool. However, it leaves the general-purpose parameters 'device' and 'skip_ui' undocumented, and given no annotations and a large 18-parameter schema, this is a notable completeness gap. The presence of an output schema does reduce the need to describe return values.

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?

With 0% schema description coverage, the description adds essential meaning by mapping each verb to its relevant parameters, specifying ISO datetime format for calendar events, and enumerating allowed mode values for navigation. However, it omits two schema parameters, 'device' and 'skip_ui', leaving their semantics unexplained, so it does not fully compensate for the low coverage.

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's purpose as 'One-call Android actions' and enumerates specific verbs with their parameters (set_alarm, set_timer, dial, compose_sms, add_calendar_event, share_text, navigate). This makes it distinguishable from UI-automation siblings like tap, type_text, and launch_app, though it does not explicitly name alternatives.

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 'One-call Android actions' implies use this tool for direct intent-style actions rather than multi-step UI interaction, and the note about dial/compose_sms only prefilling gives a specific usage constraint. However, there is no explicit guidance on when to prefer this over siblings like launch_app, open_deeplink, or other direct-action tools, and no exclusions are stated.

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