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

Annotations declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, and the description adds real context beyond them: it requires MCP write actions and without confirm:true it only previews and changes nothing. It stops short of saying what happens when a report already has a schedule (overwrite vs. conflict) or any rate/limit 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?

Two tight sentences, front-loaded with the core action and scope, followed by the write-requirement and preview caveat. No filler and nothing buried.

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?

With no output schema, the description carries the return/effect burden and largely does so by explaining the preview result and confirm requirement. It omits the effect of re-scheduling an already-scheduled report, which matters for a mutation tool.

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 100%, so every parameter (hour, dayOfWeek, dayOfMonth, frequency, recipients, confirm, previewToken, reportId) is already documented with ranges and semantics. The description adds nothing about parameter formats or interactions, which is acceptable when the schema does the heavy lifting.

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 (Schedule) plus resource (an existing report) and the scope (weekly or monthly, to a list of recipients). An agent can distinguish it from send_report (one-off delivery) and update_report_settings without opening either schema.

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 clear usage context: it schedules a recurring send of an *existing* report and requires write actions, with the preview-then-confirm flow spelled out. It never names an alternative such as send_report for immediate one-time delivery, so the agent must infer which sibling to pick.

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