fastmail_delete_masked_email

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

With no annotations, the description carries the full burden of behavioral disclosure, but it only repeats 'delete' without adding context beyond the tool name. It does not indicate whether deletion is permanent, whether it affects email delivery, or whether any confirmation or special permissions are needed.

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 clear sentence with no filler or repetition. However, it is so minimal that it borders on under-specification, contributing little more than the tool name already conveys.

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 simple one-parameter delete operation, the description is minimally viable: the agent can determine what to do and which parameter to supply. Still, it lacks critical context such as irreversibility, effects on masked email functionality, and any output or confirmation expectations, especially given that no output schema exists.

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%: the only parameter, emailId, is already documented as 'The masked email ID to delete'. The description adds no extra meaning or guidance beyond the schema, so the baseline score of 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 states a clear verb ('Delete') and a specific resource ('masked email address'), directly matching the tool's purpose. It distinguishes itself from sibling tools like list, create, and update masked email by clearly indicating a destructive removal action.

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 update_masked_email or list_masked_emails. There is no mention of prerequisites, irreversibility, or context in which deletion is appropriate, leaving the agent to infer usage solely from the tool name.

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