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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered; the description adds genuinely useful behavior the annotations cannot: scoring, the 48-hour heat window, asOf timestamp semantics, and the dedup rule that multiple outlets reporting one event counts as a single event. It still says nothing about pagination or rate limits, but the added context is substantive.

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?

It is front-loaded with purpose, then usage examples, then parameters, then return shape — a logical order with no filler. The return-shape sentence is long, and since an output schema exists it is partly redundant, keeping it just short of a 5.

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?

With annotations covering safety and an output schema covering return structure, the description only needs to add scope and selection context, which it does. The return description duplicates the output schema, so it is complete but slightly over-explained rather than optimally targeted.

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 all three parameters are already fully documented, including the defaults and maximums repeated in the description. The description adds no syntax or format detail beyond the schema, so the baseline of 3 applies.

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 names a specific verb and resource ("List recent events in AI coding agents") and adds the ranking basis (score and heat), so the agent knows exactly what the tool returns. It does not, however, distinguish itself from siblings like search_events or daily_digest, which a reader must infer from the different tool names.

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 three example questions ("what is new...", "what happened today?", "any big launches this week?") give concrete context for selecting this tool over siblings. There is no explicit exclusion or named alternative (e.g. vs search_events for targeted queries), so it stops short of a full routing rule.

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