reply_to_email

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

Annotations indicate write and destructive behavior, but the description adds no additional context about consequences (e.g., email sends irreversibly). The minimal description does not enhance understanding of the tool's behavioral traits.

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 a single, front-loaded sentence that efficiently conveys core functionality with no unnecessary words.

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 simple tool with annotations, the description provides the essential purpose and identifier. However, it omits details like optional parameters, the nature of the reply (e.g., threaded), and any prerequisites, which would be helpful given the array of sibling tools.

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?

With schema coverage at 33%, the description should compensate for undocumented parameters. However, it adds no meaning beyond what is already in the schema (e.g., message_id is described). The body and reply_all parameters receive no additional context.

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 action (Reply), the resource (existing message), and the identification method (by RFC message-id). It effectively distinguishes from sibling tools like send_email, which creates a new message.

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 tool does but offers no explicit guidance on when to use it versus alternatives (e.g., forward, reply-all). The presence of a reply_all parameter hints at a distinction, but no usage context is provided.

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