update_event

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

No annotations are provided, so the description carries the full burden. It discloses full-replace PUT semantics, the dangerous cover-clearing side effect when neither image_path nor remove_image is passed, and the need to re-upload to preserve the cover. This goes well beyond a generic 'update' statement and addresses the most surprising 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?

The description is about 90 words, front-loaded with the key purpose and method (PUT full replace). Every sentence adds operational detail, including the cover edge case and re-upload requirement. It's slightly dense but not wasteful.

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 13-parameter mutation tool with no annotations or output schema, the description covers the core update semantics, cover handling, and required inputs. It doesn't explicitly state what happens to other omitted optional fields beyond the cover, but the 'full replace' phrase and 'all the fields you want' imply they would be reset. Overall, it's complete enough to guide correct use.

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?

With 100% schema coverage, the baseline is 3. The description adds meaningful value by explaining the interplay between image_path, remove_image, and the default clear behavior, and stresses that all desired fields must be passed and event_id comes from list_events. This supplements the already-detailed schema descriptions.

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 'Update an existing event in a TimeTree public calendar (full replace — PUT)' with a specific verb and resource. It also enumerates capabilities like adding/replacing/removing cover images and changing title/time, which distinguishes it from create_event.

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 to add/replace/remove a cover image on an existing event, or change title/time/etc.', giving clear when-to-use context. It also references passing event_id from list_events, which is a necessary prerequisite. It doesn't explicitly contrast with create_event, but the 'existing event' constraint makes the boundary obvious.

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