start_timer

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

No annotations are provided, so the description must disclose behavior on its own. It only says the timer is started and provides no information about side effects, whether a timer must not already be running, ownership semantics, or what happens on success or failure.

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 short sentence with no filler. It is somewhat awkwardly phrased ('Start a running timer' could imply starting a timer that is already running), but it remains concise and front-loaded with the core intent.

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 timer-start operation, the description is minimally viable for basic invocation. However, with no annotations, no output schema, and no usage guidance, an agent would not know important behavioral details such as whether starting a timer replaces an existing one or whether user_email defaults to the current user in all contexts.

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 input schema already documents all three parameters with clear descriptions (task to time, project the task belongs to, person the timer belongs to), so schema coverage is complete. The tool description itself adds no additional parameter meaning, but the baseline of 3 is appropriate because the schema carries the burden.

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 identifies a specific action (start) and a specific resource (timer on a task), making the basic intent clear. It does not explicitly compare itself to stop_timer or get_running_timers, but the verb 'start' distinguishes it reasonably from sibling timer 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?

There is no guidance about when to use this tool versus stop_timer, get_running_timers, or get_time_report. The description relies entirely on the tool name and the reader's inference, and it does not mention prerequisites such as having an active project/task or an existing timer.

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