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

Annotations only say non-read-only, non-destructive, and non-idempotent. The description adds substantial context beyond that: admin-key authorization, billing to the organization on each start, cost-cap defaulting, self-pausing after repeated failed starts, and a 50-schedule per-organization quota. These are exactly the operational facts an agent cannot infer from structured fields.

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?

Five short sentences with zero filler, and the core action is stated first, followed by prerequisites, cost implications, and limits. Every sentence carries an operational fact that affects whether or how to call the tool.

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 8-parameter creation tool with no output schema and no annotations covering cost or quota, the description covers permissions, billing, limits, and lifecycle. The one gap is the return value: an agent is not told that the created schedule yields an identifier needed by get_schedule, update_schedule, or delete_schedule.

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 100%, so the baseline is 3; the description adds genuine semantics beyond the schema by noting that max_cost_micros falls back to a default when omitted and that the cost is billed per start. It does not clarify the cron/input interaction further, but the one concrete addition justifies going above baseline.

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 opening sentence gives a precise verb and resource combination: creates a schedule that starts a saved workflow on a timetable. This implicitly separates it from the immediate-run sibling create_run and from preview_schedule. However, the differentiation is only implicit; it never explicitly says 'not create_run', so it falls just short of the top score.

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?

'Use preview_schedule first to check the timetable' names an alternative tool and the condition that should select it, and 'Needs an administrator key' states a prerequisite. There is no explicit statement of when not to use this tool (for example, use update_schedule for changes, or create_run for an immediate one-off), which keeps it below a 5.

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