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

Annotations already convey that the operation is non-read-only and idempotent. The description adds useful context beyond annotations: it saves to the connected user's account and requires explicit confirmation before use. However, it doesn't explain what happens with a false 'confirmed' value, side effects, or why the idempotency key matters.

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 a single, front-loaded sentence with no filler. It could be more structured by separating the usage condition from the confirmation condition, but it is appropriately concise for a simple 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?

For a simple three-parameter tool with no output schema, the description covers the core use case and prerequisite. However, key parameter semantics are left to the schema (which lacks descriptions), and there is no mention of what the tool returns or how the idempotency key should be generated. It is minimally viable but has clear 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 0%, so the description must compensate. It indirectly addresses 'confirmed' by saying 'only after explicit confirmation,' but it provides no meaning for 'event_id' or 'idempotency_key.' An agent cannot infer from the description the role of the idempotency key or the expected value of 'confirmed' beyond a vague connection.

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 states a specific verb (save) and resource (one Dizko event) and clearly indicates the target is the connected user's account. It distinguishes itself from sibling tools like save_event_preferences or add_to_dizko_plan by focusing on an event save, though it doesn't explicitly name alternatives.

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?

It explicitly says 'Use this when a user confirms they want to save one Dizko event' and adds the strong precondition 'only after explicit confirmation.' This gives clear guidance on when to invoke the tool, though it doesn't mention when not to use it or point to alternative tools.

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