Determine if a cron expression, @macro, or natural interval is due now. Returns hit/miss, next and previous trigger times, and countdown without launching a real timer.
定时决策：判断「现在到点了吗」（cron / @宏 / every 30 minutes），返回是否命中、下次与上次触发时刻及倒计时。不启动真实定时器。
| Name | Required | Description | Default |
|---|---|---|---|
| now | No | 可选：以该时刻（ISO 8601）为“现在”进行评估 | |
| schedule | Yes | cron 表达式（分 时 日 月 周，如 0 18 * * *）或 @daily/@hourly 宏，或 every 30 minutes 这类自然语法 | |
| timezone | No | 按此时区评估 cron；缺省用系统时区 |
Changes observed during successful MCP inspections.
v0.2.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the burden and largely meets it: it explicitly says no real timer is started (no side effects) and enumerates the return payload (hit yes/no, next and previous trigger instants, countdown). It omits permission/rate-limit or evaluation-failure behavior, keeping it from a 5.
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 dense sentence, front-loaded with the core purpose, followed by a short clarifying clause about no real timer. Every element earns its place; slight density costs it the top score.
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?
No output schema exists, so the description correctly supplies the return values, and with no annotations it discloses the key mock/no-side-effect trait. Only the cross-tool routing and failure semantics are left thin.
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 now/schedule/timezone are already documented; baseline 3 applies. The description's mention of accepted schedule syntax echoes the schema field rather than adding new meaning, and it never mentions timezone evaluation.
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 verb+resource: it evaluates whether a schedule ('cron / @macro / every 30 minutes') is due 'now' and reports hit/last/next/countdown. That is clearly distinguishable from time-arithmetic siblings. It stops short of naming which sibling to use instead, so not 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?
Usage is implied: evaluate cron-style schedules and, per '不启动真实定时器', use it in a dry-run/mock context rather than scheduling anything real. However, it names no alternative (time_until, current_time) and gives no explicit when/when-not conditions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.