Record Split / Lap

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

Annotations are all false, so the description adds necessary behavioral details: the tool does not stop the timer, compares against PB runs, and returns delta. The announcement relay instruction is also helpful. No contradictions with annotations.

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 concise (two paragraphs), front-loaded with the main purpose, and well-structured with parameter details and return value explanation. Every sentence adds value.

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 parameters, no nested objects) and presence of output schema, the description covers all necessary context: purpose, parameters, return structure, and how to interpret results.

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 coverage is 100%, but the description adds value beyond the schema by explaining default for 'name' and the default label format 'Split N'. It also clarifies the optional nature of 'label'.

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 ('Record') and resource ('split/lap on a running timer') and explicitly distinguishes from siblings like 'timer_stop' by noting it doesn't stop the timer. The 'speedrun style' analogy further clarifies the use case.

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 usage when a running timer exists and a checkpoint is needed, but lacks explicit when-to-use or when-not-to-use guidance. No alternatives are mentioned, though the sibling list provides context. The guidance is adequate but not explicit.

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