record_performance_timeline

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

No annotations provided, so description carries full burden. It states what is recorded (memory, LCP, CLS) but omits side effects (e.g., does 'stop' clear data?) and does not disclose behavior like overlapping recordings or automatic stop on duration. No contradictions.

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?

Two efficient sentences. First sentence summarizes the three actions, second adds recorded metrics. No filler or redundancy.

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?

Missing critical context: return value for 'get' action is unspecified, and the sequential dependency (start before stop/get) is not mentioned. For a stateful tool without output schema, the description should clarify what the agent can expect from each action.

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%, so description does not need to detail parameters. However, it adds no extra context beyond the schema (e.g., explaining LCP/CLS acronyms or how interval/duration affect data collection). Baseline 3 is appropriate.

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 tool manages performance timeline recordings with three actions (start, stop, get) and specifies it records memory, LCP, CLS at intervals. This differentiates it from sibling get_performance_metrics which likely returns static metrics.

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?

No guidance on when to use this tool versus alternatives like get_performance_metrics. The description does not mention prerequisites or order of actions (e.g., start before stop/get).

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