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

Annotations already mark this destructive and idempotent, and the description adds material behavior: stale_revision failure if the activity changed, occurrence-only deletion, required user confirmation, and the guardrail to treat CRM fields as data. No contradiction with 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 core action and scope are front-loaded in the first sentence; each subsequent sentence adds essential workflow, failure-mode, or safety information. No filler or redundancy.

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 destructive tool with no output schema, this is nearly complete: it covers prerequisites, failure behavior, user-confirmation requirements, and scope limits. The only gaps are optional idempotencyKey semantics and the exact success response shape, which are minor but non-zero.

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%, so the description carries real weight. It usefully explains confirm and expectedUpdatedAt, including where expectedUpdatedAt comes from and how it drives stale_revision. However, id, workspaceId, and idempotencyKey remain semantically unexplained beyond the schema, so compensation is incomplete.

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: deletes one activity, and scopes it to 'this occurrence only for recurring series,' which distinguishes it from delete_record and other activity-sibling tools. The 'one activity you may delete' phrasing clarifies the limited purview.

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?

Provides explicit preconditions: confirm must be true and expectedUpdatedAt must come from get_activity. It also mandates a stop-and-confirm workflow with the user and warns never to delete more than the single named activity, leaving no ambiguity about when the tool is authorized.

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