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

Annotations already declare this is a non-destructive write (readOnlyHint=false, destructiveHint=false). The description adds genuine context beyond that: that a new sheet is created when sheetId is omitted and that the first column names each record. It does not mention the approval/confirmation flow, though the approvalId parameter documents that in the schema.

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?

Front-loaded with the core action and scope, then usage guidance, then column types. Every sentence carries weight, though the trailing column-type enumeration slightly overlaps the schema enum and adds length without much new information.

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 creation tool with no output schema, the description covers what is built, where it lands, and the column vocabulary. The only minor gap is not surfacing the needs_confirmation/approvalId interaction, which the schema handles instead.

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 83%, so the schema already documents most parameters, including the sheetId-omission behavior. The description's column-type list largely duplicates the schema enum, and only the 'first column names each record' detail adds meaning beyond the schema. Baseline 3 is appropriate.

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 ('Makes a table tab') and immediately distinguishes it from the sibling napkin_sheets_set_cells. It also describes the artifact concretely (typed columns, one record per row, grid/board/form views), so an agent knows exactly what is produced.

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?

Explicitly names the alternative it is not ('not napkin_sheets_set_cells') and gives the selecting condition ('lists people keep: requests, vendors, bugs, contacts'). It also states the branch behavior for sheetId omission, leaving nothing to inference.

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