bulk_action

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

Annotations already convey destructive intent, and the description adds useful behavioral detail: 'Max 100 IDs per call' and 'Returns success/failure counts.' This transcends the annotation and warns about call limits and result aggregation, though it does not explain partial failure semantics.

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 concise sentences, front-loaded with the core purpose. Every sentence provides valuable information: action list, id limit, and return format. 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?

For a batch tool with a rich schema and annotations, the description is adequate. It covers purpose, constraints, and return counts. It does not mention potential permission requirements or error handling, but these are not essential given the structured fields, and no output schema exists to explain.

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 input schema already provides descriptions for all parameters (100% coverage), including the max 100 items for 'ids' and the requirement of 'destination' for 'move.' The description replicates this info without adding new semantic value, so a baseline 3 is appropriate.

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's function with a specific verb and resource: 'Batch operation on multiple emails by UID list.' It lists supported actions and includes a max limit, distinguishing it from single-email sibling tools like move_email and delete_email.

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 term 'Batch operation' implies use for bulk actions rather than single-email operations, and the max 100 IDs constraint provides a usage boundary. However, it does not explicitly mention when to use this instead of siblings, but the clear context is sufficient.

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