Forward an email (as a draft)

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

Annotations already establish that this is non-read-only, open-world, and non-destructive. The description adds important behavioral detail: nothing is sent, the user reviews the draft in Gmail, attachments are included, and cross-account forwarding is supported.

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 three focused sentences, front-loads the core action, then adds safety and cross-account context. Every sentence adds useful information without repetition.

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 10-parameter tool with no output schema, the description is mostly complete on behavior and safety. The main gaps are parameter disambiguation and what the tool returns, such as whether it returns a draft identifier.

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 only 50% schema description coverage across 10 parameters, the description partially compensates by explaining the note, attachments, and cross-account behavior. It still leaves ambiguity around account vs sourceAccount vs from and does not clarify cc, bcc, or includeSignature.

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 states a specific verb and resource: create a draft that forwards an existing email to new recipients. It distinguishes this from generic draft creation by specifying the existing message, attachments, and optional note.

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 forwarding use case is implied clearly, and the cross-account note gives some contextual guidance. However, it does not explicitly say when to use this versus create_draft, reply, or other draft tools, nor does it state exclusions.

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