update-mail-rule

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

Annotations already include destructiveHint=true. The description reinforces mutation with 'Change writable properties' and 'save the changes'. Adds value by hinting at partial update semantics and providing a common usage scenario. Does not disclose return value details, but the absence of an output schema reduces the need.

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 sentences plus a tip, all front-loaded and no fluff. Every sentence serves a purpose: stating action, giving practical advice, and illustrating a typical use.

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 complexity of the nested schema (conditions, actions), the description provides a high-level overview and a concrete example. It does not cover error handling or retrieval of folder IDs, but the schema and sibling tools fill in. Adequate for an experienced agent.

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 83%, so the schema already documents most parameters. The description adds useful context: 'Send only the properties to change' and provides an example (isEnabled: false). This goes beyond the schema's factual descriptions.

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?

Clearly states 'Change writable properties on a messageRule object and save the changes.' This is a specific verb+resource combination. Distinguishes from sibling CRUD tools (create-mail-rule, delete-mail-rule) and provides a common use case (disabling a rule).

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 tip advises using the Inbox folder ID and to send only changed properties. It implies an existing rule is needed, but does not explicitly exclude using this for creating new rules. Context from sibling tools helps, but the description alone could be more explicit about when to use alternatives.

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