set_work_mode

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

With no annotations, the description carries the full behavioral burden. It usefully discloses that the mode gates queue/draft/send capability and that it does not affect Apple Mail, but omits persistence of the setting, effect on already-queued items, and the authorization requirement beyond what the schema already states.

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?

Three short, front-loaded sentences with zero filler; the core action is stated first and the scope caveat follows.

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 state-changing tool with no annotations, no output schema, and a non-obvious enum, the description covers the gist but leaves the meaning of each mode and the durability/scope of the change unexplained.

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 50%: user_approved is well documented in the schema, but the mode enum values (general, inbox_zero, sales_follow_up, support, deep_work) have no description anywhere and their effects are not self-evident. The description adds the queue/draft/send framing but does not explain the individual modes, so it only partially compensates for the gap.

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 (Set) and resource (local AI-mail work mode) and clarifies the scope boundary with 'This does not change Apple Mail.' It does not explicitly name the sibling get_work_mode, so differentiation is left partly to inference.

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 explains what the mode governs (queue, draft, send), which implies why one would set it, but gives no explicit when-to-use guidance, no condition for choosing a mode, and no reference to alternatives like get_work_mode.

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