Mariana Google MCP

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It successfully highlights the critical default behavior regarding invite sending, but omits other important behavioral traits such as idempotency, conflict handling, or what the tool returns upon success.

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 consists of two highly efficient sentences. The first establishes purpose immediately; the second delivers critical behavioral information about invite defaults. Every word earns its place with no 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?

Given the rich input schema (9 parameters, 100% documented) and lack of output schema, the description adequately covers the essential creation functionality and highlights the non-obvious invite behavior. It would benefit from mentioning the return value (e.g., created event ID) since no output schema exists.

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%, establishing a baseline of 3. The description reinforces the send_invites parameter's default behavior but does not add additional semantic context (format details, examples, or relationships) beyond what the well-documented schema already provides.

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 explicitly states 'Create a calendar event' with a clear verb and resource. It distinguishes itself from sibling tools (calendar_update, calendar_get, calendar_list) by focusing on creation rather than modification or retrieval.

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 description provides implied usage guidance by highlighting that it 'Does NOT send invites by default,' alerting agents to set send_invites=true if invitations are needed. However, it lacks explicit guidance on when to use this versus calendar_update or prerequisites like checking calendar_availability.

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