Google Calendar MCP Server

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

With no annotations provided, the description carries full burden. It discloses the permanent nature ('Permanently removes') and optional attendee notification, but lacks critical behavioral details like required permissions, error conditions (e.g., if event doesn't exist), whether deletion is reversible, or rate limits. For a destructive operation with zero annotation coverage, this is insufficient.

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?

Extremely concise with just two sentences that are front-loaded with the core purpose. Every word earns its place - first sentence states the action, second adds critical behavioral context about permanence and notification. No wasted words 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 deletion tool with no annotations and no output schema, the description is incomplete. It should address more behavioral aspects like permissions needed, error handling, confirmation requirements, or what happens to recurring events. The presence of sibling tools like calendar_update_event suggests this deletion might be irreversible compared to cancellation, but this isn't clarified.

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 the schema already documents all three parameters thoroughly. The description adds minimal value beyond what's in the schema - it mentions the optional attendee notification feature but doesn't elaborate on semantics beyond what the parameter description states. Baseline 3 is appropriate when schema does the heavy lifting.

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 clearly states the specific action ('Delete'), target resource ('a calendar event'), and distinguishes it from siblings like calendar_update_event (which modifies) or calendar_get_event (which reads). It goes beyond just restating the tool name by specifying the permanence of the action.

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?

No explicit guidance on when to use this tool versus alternatives like calendar_update_event (to cancel rather than delete) or calendar_get_event (to check details first). The description mentions optional attendee notification but doesn't provide context for when that should be used versus silent deletion.

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