Zapmail MCP Server

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions the tool updates mailboxes but does not cover critical aspects like required permissions, whether changes are reversible, rate limits, error handling for partial failures, or the response format. For a mutation tool with zero annotation coverage, this leaves significant gaps in understanding its behavior.

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 a single, efficient sentence that front-loads the key information ('Update multiple mailboxes') and avoids redundancy. Every word contributes to the core message without unnecessary elaboration, making it appropriately sized for its purpose.

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 complexity of a bulk mutation tool with no annotations and no output schema, the description is insufficient. It lacks details on behavioral traits (e.g., permissions, side effects), usage guidelines, and output expectations, leaving the agent with incomplete context for safe and effective tool 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?

Schema description coverage is 100%, so the schema fully documents the three parameters ('updates', 'workspaceKey', 'serviceProvider'). The description adds minimal value by hinting at the types of properties ('new names, usernames, or other properties') but does not provide additional syntax, constraints, or examples beyond what the schema already specifies.

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 ('update multiple mailboxes') and scope ('in a single operation'), specifying the types of properties that can be modified ('new names, usernames, or other properties'). However, it does not explicitly differentiate from sibling tools like 'update_mailbox_13490429e0' (singular update), though the 'bulk' and 'multiple' terminology implies a distinction.

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 no guidance on when to use this tool versus alternatives, such as the sibling 'update_mailbox_13490429e0' for single updates. It lacks context about prerequisites, constraints, or scenarios where bulk updates are appropriate, offering only a basic functional statement without usage context.

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