list_scheduled_sends

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

The annotation readOnlyHint=true already indicates a safe read operation, and the description adds context by specifying the queue source (send_email with PROTONMAIL_SEND_DELAY_SECONDS, schedule_draft) and the returned fields (id, status, sendAt). No contradictions with 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 a single, information-dense sentence that front-loads the core action and resource. It efficiently conveys the queue's origin and the purpose of the tool, though splitting it into two sentences could improve readability slightly.

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 tool with one optional parameter, read-only annotation, and no output schema, the description is sufficiently complete. It explains what is listed, where the items come from, and how the result should be used (to obtain the id for cancel_send), without requiring further detail for an agent to invoke it correctly.

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 schema covers the only parameter (status) with a clear description ('Filter to one status. Omit to list everything.'), so the description does not need to add much. It mentions status as part of the output, but this is not additional parameter semantics beyond the schema's 100% coverage.

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 lists every item in the local undo-send/scheduled-send queue, including id, status, and sendAt. It distinguishes itself from siblings by explicitly mentioning the use case of rediscovering the id for cancel_send, making its purpose unmistakable.

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 clear context for when to use this tool, specifically to recover a lost id needed for cancel_send. It does not explicitly exclude alternatives, but the reference to cancel_send and the queue origin (send_email with delay, schedule_draft) implies the appropriate usage scenario.

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