mailbox-settings

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

The description discloses idempotency (safe to retry), PATCH-style merging with existing state, and return behavior for set actions. This goes beyond the annotations' idempotentHint and readOnlyHint, adding valuable context about how updates behave and what the agent can expect.

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 dense but well-organized, starting with the primary purpose and idempotency note, then breaking down each action with its relevant parameters. It is long but every sentence contributes useful information without redundancy.

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 tool with 12 parameters, 3 actions, and no output schema, the description comprehensively covers retrieval with section filtering, configuration of auto-replies and working hours, and return behavior for set actions. It is sufficiently complete for an agent to invoke 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?

Even with 100% schema coverage, the description adds significant value by mapping parameters to specific actions (e.g., startTime/endTime/daysOfWeek for set-working-hours, enabled/startDateTime/endDateTime for set-auto-replies) and clarifying defaults (action=get). This reduces ambiguity for parameter selection.

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 reads or updates mailbox-level settings, with specific sub-actions (get, set-auto-replies, set-working-hours). This distinguishes it from sibling tools like search-emails or list-events, which handle 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?

The description provides clear context for when to use each action (e.g., action=get to retrieve settings, action=set-auto-replies for out-of-office), but does not explicitly mention alternatives or when not to use this tool. It lacks explicit exclusions, but the tool's purpose is well-defined.

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