List locally enabled sender addresses, the default address, and the saved sender name. Use these to choose a valid identity Apple permits for SMTP sending.
List locally enabled sender addresses, the default address, and the saved sender name. Apple validates sending permission during SMTP submission.
| Name | Required | Description | Default |
|---|---|---|---|
| arguments | Yes |
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so the safety profile is covered. The description adds genuine context beyond that: the list reflects only local enablement, and actual sending permission is validated by Apple at SMTP submission time, warning the agent that a listed sender is not a guarantee of sendability.
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 tight sentences with zero waste. The list of returned items is front-loaded, and the behavioral caveat about Apple's SMTP validation follows as supporting context.
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, no-argument read tool with no output schema, the description carries the return-value burden and does so by naming the three returned items (enabled senders, default address, saved name). The only minor gap is it doesn't describe ordering or whether the list can be empty.
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?
There are effectively no meaningful parameters – the single 'arguments' field is an empty object with 0% schema description coverage. With nothing to document, the baseline of 4 applies; the description neither adds nor needs parameter detail.
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?
States a specific verb (List) and resource (locally enabled sender addresses) and enumerates what is returned: sender addresses, default address, and saved sender name. This clearly distinguishes it from siblings like mail_folders or mail_search, which operate on different resources.
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?
Usage is implied by the noun phrase 'locally enabled sender addresses' – an agent can infer this is the tool to consult for available senders. However, there is no explicit when-to-use statement, no mention of alternatives, and no exclusions or prerequisites for calling it.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.