create_timeline_event

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

Annotations already declare this is a non-read-only, non-idempotent, non-destructive write. The description adds nothing beyond that profile — no mention of permissions, side effects (e.g., that a missing lane name causes a new lane to be created), or the open-world resource resolution behavior. The 'full story' link sentence is the only behavioral flavor, and it maps to a parameter.

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?

Two short sentences, front-loaded with the action, with no filler. It is efficient but arguably under-specified for a 15-parameter mutation tool, which is a completeness problem rather than a verbosity one.

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 15-parameter, non-idempotent, open-world creation tool with no output schema, the description is far too thin. It does not explain the two required parameters' roles, the optional link relationship, or what the caller gets back, leaving the agent to rely entirely on the schema.

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 67%, so the schema already documents most parameters (start/end calendar formats, lane creation, resource resolution, project/document defaults). The description reinforces only the `link` parameter's intent ('page that tells the full story') and adds nothing for the undocumented color, is_hidden, icon_glyph, end_minutes, and show_on_calendar fields.

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 names a specific verb and resource ('Add an event to a timeline document'), which clearly separates it from update_timeline_event and delete_timeline_event. However, it does not distinguish itself from other creation tools beyond the obvious verb, relying on the noun to carry differentiation.

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?

There is no statement of when to use this tool versus alternatives, no preconditions, and no mention of update_timeline_event for modifying an existing event. The only hint ('Link it to the page that tells the full story') describes a parameter rather than tool selection.

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