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

With no annotations, the description carries the behavioral load and does well on several axes: results are newest-first, events are pre-derived and de-duplicated, and each carries a severity grade, which matters for interpreting output. Gaps remain on pagination/truncation behavior (the schema caps limit at 200 but the description says nothing about what happens beyond it) and on whether the feed depends on monitors being configured.

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 sentences, no filler, with the content summary front-loaded and the 'derived events, not raw changes' clarification following as a useful reframe. The opening phrase 'What was worth telling someone' is stylish at some cost to crispness, but the passage is otherwise tight.

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 four-parameter read tool with no annotations and no output schema, the description covers what kinds of events exist and their ordering, but does not describe the shape of an event record (fields, severity semantics) or scoping/auth requirements ('across this account' is the only hint). Adequate for selection, thin for interpretation.

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 and min_severity have descriptions, limit and since_days have only defaults and bounds. The description adds nothing concrete about parameter usage — it references severity grading, which loosely connects to min_severity, but never explains the type string format or the meaning of the since_days window, so it does not compensate for the undocumented half of the schema.

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 conveys a specific resource — a derived event feed for the account — and gives concrete examples (certificate changes, security headers disappearing, deindexed pages, monitor flaps). It also distinguishes itself from the 'raw change stream' and implicitly from the sibling asset tools. It loses a point because it never uses an explicit verb like 'list' or 'retrieve', so the agent must infer that this is a queryable feed.

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: use this to see notable occurrences across the account rather than raw changes. But there is no explicit when-to-use versus the sibling tools (plane_assets, monitor_*), and no guidance on when to narrow with type, min_severity, or a shorter since_days window versus taking the default 7-day view.

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