create_email_draft

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It does clarify that the tool only drafts (does not send) and that it opens Apple Mail, but it does not mention whether Apple Mail must already be running, or any side effects like app activation. This is adequate but not highly transparent.

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 a single, well-structured sentence that front-loads the core purpose and immediately lists the optional parameters. No unnecessary words or repetition.

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 tool with three optional parameters and no output schema, the description provides sufficient context about what the tool does and what inputs it accepts. It could mention behavior when all parameters are omitted, but that is minor given the simplicity.

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 100%, so the baseline is 3. The description goes beyond the schema by explicitly listing all three parameters ('recipient', 'subject line', 'body message content') and reinforcing they are optional, which adds meaningful context for the agent.

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 function: 'Drafts and opens an email in Apple Mail' with specific optional parameters (recipient, subject, body). It uses a specific verb ('drafts' and 'opens') and names the target resource (Apple Mail email), which distinguishes it from sibling tools like 'create_note' that operate on different content.

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 implies the tool is for composing email drafts but does not explicitly state when to use it versus alternatives or when not to use it. There is no direct sibling email tool, so the usage context is somewhat implied rather than explicitly guided.

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