create-rule

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It clearly warns that the rule acts automatically on real mail, including delete/move actions, on an ongoing basis, and instructs the agent to confirm with the user. This goes beyond the schema and reveals critical side effects.

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 well-structured with clear sections (Use when, Returns, Do not use when, Safety). Every sentence adds value, and the length is appropriate for a tool with nested parameters and significant side effects. No filler or 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?

Given the tool's complexity (nested objects, 5 parameters, no schema descriptions), the description covers purpose, usage, return value, and safety implications. It also references list-rules for deduplication, making it sufficiently complete for an agent to select and invoke the tool 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 description coverage is 0%, so the description must compensate. It explains conditions (field/operator/value), action types, and matchAll semantics. However, it omits some parameters (e.g., enabled, moveToAccount, name) and does not detail the structure of the actions object fully. Coverage is moderate but not exhaustive, warranting a mid-range score.

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 creates a new Mail rule with conditions and actions, using a specific verb and resource. It distinguishes itself from sibling tools by explicitly naming alternatives (enable-rule, disable-rule, delete-rule) and providing a 'Do not use when' clause.

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 explicit 'Use when' and 'Do not use when' guidance, naming exact sibling tools and their purposes. It also advises using list-rules to avoid duplication, which is actionable context for an agent deciding when to invoke this tool.

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