events.tail

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

No annotations are provided, so the description carries the full burden. It usefully discloses the event taxonomy and that delivery is push-based rather than polled. It does not state return shape, retention window, ordering, or how n interacts with the stream, leaving meaningful behavioral gaps for a tool with zero annotation coverage.

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: it names the resource first, then enumerates types, then gives the use-case and delivery model. Dense but no filler. The em-dash structure packs a lot without padding.

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?

For a simple 2-param, all-optional read tool with no output schema, the description is adequate: it names the event types and the push delivery model. But with no annotations and no output schema it should say more about what an event record looks like and how many are returned beyond the default n=20.

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 50%: 'type' is documented but 'n' has none. The description's parenthetical list (page_change/app_start/app_crash/visual_change) supplies concrete filter values the schema's 'type' field lacks, which is genuine added meaning. It says nothing about the 'n' limit or ordering, so the baseline of 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?

It states a specific verb+resource: '最近的设备事件' (recent device events) and enumerates the concrete event kinds (page_change/app_start/app_crash/visual_change). This is far more informative than a bare 'tail'. However, it does not explicitly contrast itself with close siblings like events.snapshot, events.capture, or events.wait, so differentiation relies on inference.

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 phrase "刚才发生了什么"的场景感知 (situational awareness of 'what just happened') and '推送非轮询' (push, not polling) imply when it is useful, and the push-vs-poll hint gestures at behavior. But there is no explicit when-to-use/when-not and no named alternative among events.snapshot/events.capture/events.wait, so guidance stays implied.

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