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

No annotations are provided, so the description carries the full burden. The description discloses the behavior that the tool returns options rather than executing anything, and emphasizes 'ready-to-install entries,' which informs the agent about the nature of the output. However, it doesn't detail the structure of these options or how installation works, but that might be covered by the tool's output.

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 very concise at two sentences, with no filler. It front-loads the purpose ('make check-ins happen on a timer') and provides essential context without wasting words. Every sentence earns its place.

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 tool has no parameters and no output schema, the description provides enough to understand what the tool does and why. It explains the problem (agent cannot wake itself) and the solution (returns options). It might benefit from mentioning that the output is verbose or the format, but since it returns instructions, the description covers the essentials.

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 tool has zero parameters, so the schema provides no parameter information. The description compensates by explaining the conceptual purpose, which is sufficient since there are no parameters to describe. This is a baseline 4 because the description adds meaning to the tool's function even without parameters.

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 that the tool returns options for scheduling check-ins, specifically via an external timer. This is a distinct purpose, and the phrase 'how to make check-ins happen on a timer' explains the tool's role. However, it doesn't explicitly differentiate from sibling tools like 'list_future_events' or 'heartbeat', but the purpose is clear enough.

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 implicitly explains when to use this tool: when an agent needs to set up recurring check-ins and cannot do so via self-waking. It also provides a clear constraint ('An agent in a chat cannot wake itself') that explains why the tool exists. It doesn't explicitly mention when not to use it, but the trigger context is clear.

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