Messages Send Message

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

Annotations indicate destructiveHint=true and idempotentHint=false, but the description adds no behavioral context beyond that, such as whether messages are actually delivered, permission requirements, or side effects. With annotations present the bar is lower, but the description still contributes nothing.

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 short but not usefully concise; it is under-specified boilerplate that repeats the tool name. It earns no credit for brevity because it omits substantive information rather than summarizing it.

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?

Despite a simple two-parameter signature, the tool performs a meaningful side-effectful action (sending a message) and has a destructive hint. The description fails to explain sender identity, recipient format, delivery behavior, or any prerequisites, leaving the agent unable 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?

Schema description coverage is 0% and the description provides no explanation of what 'recipient' or 'text' mean in practice, such as expected formats, phone/email resolution, or constraints. This violates the need for the description to compensate when the schema is bare.

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 only restates the tool's name and says it is a 'Delegated Apple domain tool' exposed through Apple-Tools-MCP; it does not state what sending a message entails. The title 'Messages Send Message' carries the only real meaning, but the description itself adds no functional clarity.

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 like messages_reply_in_conversation or messages_send_attachment. The description provides no context for selecting this tool over its siblings.

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