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

Adds meaningful behavior beyond annotations: omitted fields stay unchanged, empty strings clear fields, and start_time omitted means all-day. These are useful mutation semantics even though annotations already declare destructive and idempotent behavior.

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?

Front-loads the core action and affected fields, then adds precise mutation semantics in a compact form. Every clause conveys actionable information with no waste.

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 10-parameter mutation tool with no output schema, the description covers update behavior, omission semantics, clearing behavior, and time handling. It could say more about authentication or irreversible effects, but annotations already flag destructiveness.

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 coverage is 70%, and the description adds important semantics not fully captured in the schema, including local-time handling, all-day behavior when start_time is absent, and empty-string clearing. It does not explain every field, but it meaningfully supplements 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?

States a specific verb and resource: updates shared Event details, and explicitly lists the affected fields (title, date/time, location, description). It is clearly distinguishable from sibling tools like set_availability, set_rsvp, or add_place.

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?

Gives a clear usage condition: use when the user sets or changes agreed event details or renames the plan. It does not name alternatives or exclusions, but the context is sufficient for correct selection.

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