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

Annotations already cover the safety profile (destructiveHint=true, idempotentHint=true), so the bar is lower; the description still adds the auth requirement (config:write), the partial-update semantics that explain the idempotent hint, and the external SHIP API dependency with a doc link. It does not explain what 'destructive' means here (e.g. that labels replaces the existing list), leaving one gap.

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?

Three sentences, no filler. The mutation scope and partial-update behavior are front-loaded, followed by the schedule coupling rule and then the operational prerequisites.

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 an 11-parameter mutation tool with no output schema, the description covers update semantics, cross-field constraints, capability auth, and backend dependency. Remaining unknowns (failure behavior on an unknown id, replacement semantics for labels) are handled by the schema rather than the prose, so it is nearly complete.

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, but the description adds genuine cross-field semantics the schema only states locally: the interval/time/timezone coupling and the weekday/dayOfMonth conditionality. That is meaning beyond the per-property 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?

States a specific verb ('Patch') plus resource ('a scheduled task') and enumerates the mutable surface (name, prompt, schedule, skip-guard, enabled state). The 'only the fields passed are changed' clause distinguishes it from create/delete/run siblings without needing their schemas.

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 real usage rule — schedule changes require interval/time/timezone set together, plus weekday or dayOfMonth as the interval dictates — and names the config:write capability prerequisite. It stops short of explicitly naming when to prefer a sibling (e.g. run_scheduled_task or delete_scheduled_task), so it lands at clear-context-without-exclusions.

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