Update calendar event

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

Annotations already flag this as a destructive, non-read-only mutation. The description adds the key behavioral trait of full replacement ('replace all editable fields') and the constraint that all fields must be provided, which is useful beyond the annotations. However, it doesn't discuss side effects or response behavior, keeping it slightly above baseline.

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 concise, with the purpose front-loaded in the first sentence and an API link for details. However, the misleading 'all fields required' statement reduces its overall value, preventing a perfect score.

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 11 parameters, no output schema, and a destructive mutation, the description is too sparse. It doesn't mention return values, error conditions, or clarify the required/optional distinction, and it contains a misleading requirement statement. The API link mitigates but doesn't compensate for these gaps.

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% (baseline 3), but the description's claim 'All event fields are required' directly contradicts the schema, where only 5 of 11 parameters are required and others have defaults. This is misleading and could cause an AI to think it must supply optional fields, adding harmful semantics beyond the schema.

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 tool's action: 'Replace the editable fields of an existing kalender.digital event.' The verb 'replace' plus 'existing' differentiates it from create_event (for new events) and delete_event (for removal), making the purpose unambiguous.

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 phrase 'existing event' provides clear context that this tool is for modifying already-created events, implying it should not be used for creation. However, it doesn't explicitly name alternative tools like create_event or state 'use create_event for new events,' so it lacks explicit when-not and alternatives.

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