apple_facetime

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states 'Make FaceTime calls' and does not mention the confirmation requirement for protected actions, the preview behavior when `confirm` is false, potential side effects, or any prerequisites (e.g., FaceTime app installed, user logged in). This is a significant gap for an action that may require confirmation.

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 two short sentences, front-loading the main purpose first, then listing the actions. It is extremely concise with no wasted words, and both sentences contribute useful information. This is appropriately sized for the tool's simplicity.

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?

Given the tool's simplicity and a well-documented schema, the description is minimally viable but lacks key context like the confirmation flow and what happens on execution. There is no output schema, so the agent must infer return behavior. The schema covers parameter details, but the description does not enrich the contextual picture enough to reach a higher score.

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 input schema already provides 100% coverage of all three parameters with descriptions. The tool description adds no extra meaning beyond the schema; it merely restates the action names ('call (video), audio') which map to the enum. Baseline 3 applies because the schema does the heavy lifting.

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 makes FaceTime calls and enumerates the two actions ('call' for video, 'audio' for audio). It uses a specific verb and resource, making the purpose obvious. However, it does not explicitly differentiate from siblings beyond the unique FaceTime resource, so it earns a 4 rather than a 5.

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?

There is no guidance on when to use this tool versus alternatives. The description does not mention any exclusions, prerequisites, or sibling tools that might serve similar communication needs (e.g., apple_messages). The usage context is only implied by the tool name and resource.

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