Mark Email Forwarded

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

Beyond annotations (idempotentHint=true, destructiveHint=false), the description adds valuable behavioral context: the default value, the requirement for sourceFolder to avoid silent no-ops, and the warning against using 'All Mail' as source. No contradictions with annotations.

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 concise sentences: first defines purpose, second provides key usage guidance. Every sentence is necessary and adds value. No superfluous text.

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?

The description covers the essential behaviors (keyword, default, folder scoping) and integrates with the forward tool context. With output schema available (not shown), return values are presumably documented, so the description is sufficiently complete.

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 50% (descriptions for account_id and sourceFolder). The description adds only marginal value: it repeats the default for 'forwarded' (already in schema) and adds a warning about 'All Mail' for sourceFolder. No new info for emailId or account_id.

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 verb 'set or clear' and the resource '$Forwarded keyword on an email', explicitly linking it to the forward tool. This distinguishes it from sibling tools like mark_answered or mark_email_read.

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 guidance on the default value for 'forwarded' and when to use 'sourceFolder' (when UID comes from a folder other than INBOX). However, it does not explicitly contrast this tool with alternatives or specify when not to use it, leaving some ambiguity.

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