Bulk Star/Unstar Emails

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

The description adds value beyond annotations by stating that it emits progress notifications and returns success/failed counts. It also reveals the behavioral nuance of sourceFolder scoping. Annotations already indicate non-readOnly and non-destructive, and description complements them. It does not explicitly mention idempotency, but idempotentHint is true.

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 sentences with no redundancy. Each sentence serves a distinct purpose: stating the core action, mentioning side effects (progress notifications, return counts), and providing crucial usage guidance. The key information is front-loaded.

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 (bulk operation with folder scoping) and the presence of an output schema, the description covers main behavioral aspects and the critical sourceFolder parameter. It could be more explicit about when to use this tool versus the singular star_email, but overall it provides sufficient context for correct invocation.

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?

The description compensates for the missing schema description of isStarred by implying its role (star/unstar). It also reinforces the critical sourceFolder parameter with detailed usage guidance, adding meaning beyond the schema. Schema coverage is 75%, and the description fills gaps effectively.

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 'Star or unstar multiple emails,' specifying the verb (star/unstar) and resource (emails) in bulk. It also mentions progress notifications and return counts, adding clarity. It effectively distinguishes from sibling tools like star_email by emphasizing the bulk aspect.

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 guidance for using sourceFolder when UIDs come from a folder other than INBOX, including a warning about 'All Mail.' However, it does not contrast with the singular star_email tool or specify when not to use this tool, leaving some room for ambiguity.

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