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

With no annotations, the description carries full behavioral disclosure. It explains that the tool returns a run id, that the run succeeds only after the phone executes the command, and that get_ip and clipboard_get return result.value. It also notes op-specific fields are only sent when provided, which is important. It does not mention error handling or side effects beyond the listed ops, but the ops themselves (e.g., reboot, clear_photos) are self-evidently destructive.

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 efficiently structured with a clear purpose, a compact list of operations, and a concise note on return behavior. It front-loads the core action and does not waste words, though the op list could be considered slightly long.

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 essential return behavior (run id and result.value for specific ops), the slot requirement, and all operations. It does not elaborate on error cases or timeouts, but for a command tool with no output schema, it provides sufficient context for correct invocation.

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 coverage is 100%, so the baseline is 3. The description adds value by mapping each op to its relevant parameters (text, url, level, on) and clarifying that these fields are only transmitted when provided. This goes beyond the schema's individual parameter descriptions and helps the agent understand conditional usage.

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 sends a device command to a farm phone and enumerates specific supported operations. This makes the purpose unambiguous and distinct from siblings like phone-ocr-tool or phone-snapshot-tool, though it does not explicitly reference 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 description provides a critical precondition (the slot must be cast/live) and lists operations, implying when to use the tool. However, it does not explicitly contrast with sibling tools like phone-control-tool or state when not to use this tool, leaving some inference to the agent.

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