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

Adds useful context beyond the annotations: no invitations are sent, the new record is returned, and it maps to POST /events. Annotations already declare it is a non-read-only, non-idempotent, non-destructive open-world write, so the remaining gaps are minor.

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?

Four short sentences, front-loaded with the critical 'WRITE' signal. Every sentence adds useful information with no filler.

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 five-parameter create tool with no output schema, the description covers the key behavioral facts: write operation, no invitations, return value, and endpoint. Required fields are left to the schema, which is acceptable, though optional parameter behavior remains underspecified.

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?

The description gives no parameter-level guidance, while schema coverage is only 60%. The schema still documents required title and startDate and provides formats for dates, but isAllDay and descriptionHTML are left undocumented in both places.

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: 'add a calendar event.' The purpose is immediately distinguishable from the sibling plutio_list_events, which lists rather than creates events.

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 'WRITE: add a calendar event' phrasing implies when to use it, but it does not explicitly say when to prefer it over alternatives or mention prerequisites. Usage is inferable but not actively guided.

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