Timer List Tool

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It does indicate a read-only listing operation and the return shape (list with count), but it does not mention privilege requirements or whether inactive timers are included. These omissions are not misleading for such a simple listing tool.

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 short and front-loaded with the core action. The 'Returns:' line adds a small amount of detail but is slightly redundant with the first sentence. Overall, it is concise and purposeful.

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 parameterless listing tool with an output schema, the description adequately defines what the tool does and what it returns. It does not specify timer state filtering or sorting, but those details are not required given the simple scope and available output schema.

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?

There are zero parameters, so the description has no parameter semantics to add. The baseline of 4 applies because there are no arguments that could be ambiguous or need clarification.

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 ('List') with a concrete resource ('systemd timers') and details the key returned data ('next and last elapse times'). This clearly differentiates it from sibling unit/status tools by focusing on the timer resource.

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 this tool is for listing systemd timers and their elapse times, but it does not explicitly state when to prefer it over unit_list_tool or other sibling tools. No exclusions, prerequisites, or alternative routing guidance is provided.

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