schedule_send

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does disclose a key limitation: execution only occurs while the server process is alive. This is valuable and beyond what the schema provides, but it does not address other behavioral aspects such as persistence, cancellation, or errors.

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 sentence with no wasted words. It front-loads the core purpose ('定时发送') and then packs the most critical behavioral and parameter caveats into the parenthetical. Efficiency is strong, though it could be slightly more structured for readability.

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 output schema exists, return values need not be explained. The description covers the most critical constraints (send_at ISO format, server lifetime, to required). However, it misses some context such as whether scheduling persists across restarts, how conflicts are handled, or any auth requirements. It is acceptable for a simple tool but has clear gaps for a scheduling feature.

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 0%, so the description must compensate. It adds crucial semantics for send_at (ISO time) and a non-empty constraint for 'to'. However, it leaves subject and body undocumented, and it doesn't explain the format of 'to' beyond non-empty, even though the schema shows it as an array of strings.

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 '定时发送' (scheduled send), which clearly indicates the tool's function is to schedule a send rather than send immediately. This differentiates it from immediate siblings like send_email and batch_send, though it does not explicitly name the email resource or distinguish itself from other scheduling-related tools.

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 implies use for delayed sending via the phrase '定时发送', and the parenthetical about server process lifetime provides an important condition. However, it does not explicitly state when to choose this over alternatives like send_email or batch_send, nor does it mention any exclusions.

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