schedule_message

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

With no annotations, the description carries the full behavioral disclosure burden, but it only restates the basic scheduling action. It does not mention that the message is stored as a scheduled entry, that it can be later listed/deleted via sibling tools, that post_at must be in the future, or any permission/rate-limit considerations.

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 filler, front-loading the core verb and resource and immediately stating the distinguishing future-time behavior. Every word contributes meaning.

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?

The tool is simple and all parameters are documented, but because there are no annotations and no output schema, the description leaves gaps about the response shape, cancellation/listing behavior, and scheduling constraints. It is minimally adequate but not fully complete.

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 all three parameters are already documented in the schema. The description adds no additional parameter-level semantics, which matches the baseline of 3.

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 uses a specific verb ('Schedule') and resource ('a message') with a clear temporal qualifier ('at a future time'), directly distinguishing it from the sibling send_message tool. An agent can immediately understand that this is the delayed-send counterpart.

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 clearly implies when to use it: when a message must be delivered later rather than immediately. It does not explicitly name alternatives or state when not to use it, but the contrast with send_message is evident from the future-time qualifier.

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