apply_mail_setup

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

With no annotations, the description bears full responsibility for disclosing effects. It warns that the action may replace or combine an existing record, emphasizes that modifying existing data affects someone else's live mail, and indicates that explicit operator approval is needed in those cases. This is adequate though not exhaustive.

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 concise and front-loads the core purpose, then adds necessary approval caveats. Some phrasing is a bit cryptic ('somebody put there on purpose', 'someone else's live mail') but it does not waste words and remains understandable.

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?

Given the tool's mutation-like nature and the absence of an output schema, the description provides enough context about when to call it, what it may change, and the approval requirement. It does not describe return values or failure modes, but these are not essential for an agent to 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 coverage is 100%, and the descriptions add useful constraints beyond basic types: `client` specifies the registered name and credential resolution, `plan_id` ties to the planning output and cross-client rejection, and `approved` clarifies default behavior and when it is required. This exceeds the baseline given full schema coverage.

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 identifies the tool's action as carrying out a plan produced by `plan_mail_setup`, which distinguishes it from the planning sibling tool. It names the specific resource (a mail setup plan) and the operation (apply/execute).

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 gives explicit guidance to show the plan to the operator before calling, and states when `approved` is required (when the plan would replace or combine an existing record). It could more explicitly contrast with `plan_mail_setup`, but the instruction to call only after showing the plan is clear.

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