mail_manage_email_labels

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

The description discloses the operation (add/remove keywords), examples of effects (pin, mark read, etc.), and the constraint that at least one of add or remove must be provided. However, it lacks details on idempotency, error cases, or permissions, which would be helpful given no 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?

The description is concise and well-structured. It starts with the purpose, then provides usage guidance, common keywords, the constraint, and parameter details in a logical order. No unnecessary information.

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 moderate complexity (3 params, no nested objects, output schema exists), the description covers all parameters and behavior adequately. It could mention the existence of the output schema but is otherwise complete for a management tool.

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 0% schema description coverage, the description fully compensates by explaining each parameter: email_ids as 'List of JMAP email IDs to update,' and add/remove with examples and common keywords. It also adds a constraint ('At least one of add or remove must be provided') that is not present in the schema.

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: 'Add or remove keywords/labels on one or more emails.' It provides specific examples (pin/flag, mark read/unread, apply custom labels) and distinguishes itself from sibling tools like mail_pin_email and mail_mark_email_read by being a general-purpose label management tool.

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 when to use the tool ('Use this to pin/flag, mark read/unread, or apply custom labels') and what common keywords to use. It implicitly suggests this tool can replace more specific sibling tools, though it does not explicitly list alternatives or when not to use it.

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