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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation profile is covered. The description adds real value beyond that by specifying exactly what survives the operation — formatting and the rows themselves — which is the key behavioral question for a 'clear' tool. It omits auth requirements, rate limits, and whether the operation is reversible.

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, both front-loaded: the semantic effect first, the safety requirement second. No filler, no repetition of the title.

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 destructive, no-output-schema tool the description covers effect and confirmation adequately, and the absence of return values is fine. It falls short on the three undocumented parameters, where an agent gets no help on range syntax or workbook/sheet identification.

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 only 25% — just 'mailbox' is documented — and the description adds nothing about workbookId, sheet, or range. For a destructive tool, the missing guidance on range notation (e.g. A1 style) and sheet naming is a meaningful gap that the schema does not fill.

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: 'Empty the values in a range' on an Excel workbook, which is concrete and not a restatement of the title. It does not, however, distinguish itself from the close siblings clear_google_sheet_range (other platform) or update_excel_range (overwrite vs empty), leaving that routing to the agent's inference.

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 confirmation instruction ('Ask the user to confirm before clearing anything they did not just create') is genuine usage guidance about a prerequisite step. However, it gives no when-to-use vs alternatives guidance, e.g. clear_google_sheet_range or update_excel_range, so the routing question is left implied.

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