agent_clock

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

With no annotations, the description carries the full burden. It usefully discloses that the return is cumulative elapsed time plus a Chinese-readable duration, and the '会话级' framing hints at session-scoped persistence. However, it says nothing about destructive behavior of reset, restart semantics of start on an existing clock, or multi-clock isolation, leaving notable behavioral gaps.

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?

A single front-loaded sentence packs the resource and all five action meanings with essentially zero filler. Slightly dense but appropriately sized for the tool's scope.

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?

There is no output schema, so the description must cover returns — and it does, naming cumulative timing and a readable duration. Given a 4-parameter, single-required-param stateful tool with full schema coverage, the only real omission is guidance on sibling selection and mutation/restart semantics.

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 100%, so the schema already documents action, clock_id, timezone, and session_id in detail. The description merely repeats the action glosses without adding format, default, or interaction semantics (e.g., how clock_id and session_id combine), so it lands at the baseline.

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?

States a specific resource ('会话级计时器') and enumerates all five operations with their Chinese glosses, so an agent immediately knows this is a stateful session timer rather than a one-shot time query. It does not name any sibling (duration_elapsed, current_time) to distinguish scope, so it falls short of a 5.

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 action enumeration implies the operating modes, but there is no explicit when-to-use guidance or routing against siblings like duration_elapsed or current_time. Usage must be inferred from the verb list rather than stated.

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