stop_timer

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

With no annotations, the description carries full burden. It discloses that the tool stops the timer, logs the entry, and accepts optional notes, but fails to mention behavioral traits like what happens if no timer is running (error?), whether the action is irreversible, or any permissions needed. Minimal disclosure for a mutation 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 a single short sentence, which is concise, but it sacrifices completeness. The core action is front-loaded, but important details about parameters and usage are missing. It could be restructured to include more info without being verbose.

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's simplicity (2 optional params, no required fields, output schema exists), the description is somewhat adequate but lacks depth. It doesn't explain the return format or behavior edge cases. For a simple timer stop, it's minimally viable but leaves gaps.

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 description must compensate. It explains the 'notes' parameter is optional and for adding notes, but completely omits the 'api_key' parameter, leaving its purpose and usage unclear. Only half the parameters get meaningful context.

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 the verb 'stop' and resource 'timer', and distinguishes it from siblings like start_timer by specifying it stops the running timer. It explicitly says 'log the time entry' and 'optionally add notes', which is specific and unambiguous.

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 does not explicitly state when to use this tool over alternatives or provide exclusions. It implies usage when a timer is running, but no guidance on prerequisites or conditions is given. Sibling names help infer context, but explicit direction is missing.

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