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

Annotations already signal readOnlyHint and non-destructive behavior. The description adds meaningful context: it returns events from multiple sources, lists the returned fields, orders events 'soonest first,' and instructs the agent to answer from this list rather than chat history. It does not mention absence/pagination behavior, but that is a minor gap given the annotations.

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?

The description is longer than average but front-loads the primary use case, then delivers return shape and window behavior in dense, information-packed sentences. Every sentence contributes value and there is no filler.

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, but the description enumerates the returned fields (id, title, starts_at, ends_at, all_day, source), the ordering, the window semantics, and the data sources. It also tells the agent to prefer this list over chat history. For a read-only list tool with two optional parameters, nothing essential is missing.

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 100% and both parameters are already described with types and defaults. The description restates the window semantics ('default 7, at most 62') but adds little beyond what the schema provides, so the baseline 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?

The description opens with a specific verb and resource: 'Use this when the member asks what is on their calendar or schedule' and identifies the resource as 'the member's own Connections calendar.' It further distinguishes itself from siblings by listing aggregated sources such as hosted events, note deadlines, and connected Google Calendar.

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?

It explicitly enumerates trigger phrasings: 'what is on their calendar or schedule, whether they are free or busy... today, tomorrow or this week, or when something on their calendar is.' It does not explicitly name alternative tools or when-not conditions, but the trigger list is clear enough for routing.

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