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

Despite annotations already declaring destructiveHint/idempotentHint/openWorldHint, the description adds substantial non-obvious behavior: soft-delete to trash with 30-day permanent removal, no restore via these tools, assignee notification, Google Calendar cancellation email for non-repeating events, and stale_revision refusal on retry. This is exactly the behavioral context annotations cannot express.

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?

Front-loads what the tool does before the preconditions, and nearly every sentence adds operational value (trash retention, retry semantics, confirmation protocol). The trailing untrusted-content warning is boilerplate but security-relevant, and the description is long for a five-parameter tool.

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 no output schema, the description still covers side effects (notification, calendar cancellation) and failure modes (stale_revision), which is what an agent needs for a destructive tool. It omits auth/permission requirements and any workspace-scoping caveat beyond what the schema states.

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 only 20% (only workspaceId is documented in-schema), so the description must carry more. It clarifies the semantics of confirm ('Needs confirm: true') and expectedUpdatedAt (source and stale_revision retry behavior), but says nothing about idempotencyKey or the id field format, leaving part of the gap unfilled.

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 and resource ('Moves one activity ... to the trash') and immediately narrows scope ('only this occurrence of a repeating activity'). An agent can distinguish it from update_activity, complete_activity, and delete_record without opening any schema.

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?

Gives strong pre-call guidance: requires confirm:true and expectedUpdatedAt sourced from get_activity, plus an explicit protocol to name the activity to the user and get a go-ahead in the same turn. It stops short of naming alternative siblings (e.g., use update_activity to edit rather than delete), so it is clear context without explicit alternatives.

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