Format cells

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

Building on annotations, the description adds valuable behavior: partial updates preserve untouched formatting ('making a header row bold does not flatten the number formats under it'). It also discloses color syntax rules and that the number format code determines date display. It does not contradict the idempotent/destructive hints, though it could have warned about merge data loss itself.

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 with no filler: the operation is front-loaded, the most important behavioral nuance follows, and supporting conventions (colors, number format codes, file types) are packed efficiently at the end.

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 18-parameter tool, the description covers the operation categories, partial-update behavior, color and number-format conventions, and supported file types. The parameter schema and output schema already carry the remaining details, so nothing critical is missing for an agent to call it correctly.

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, but the description adds cross-cutting meaning: hex colors must omit the leading hash, and number_format is an Excel code that also controls date rendering. This is useful shared semantics that apply to several parameters and is not obvious from individual schema 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?

The description opens with a specific verb and resource ('Changes how a range looks') and enumerates the exact formatting operations it covers. This clearly separates it from value-editing siblings like xlide_write_cells by emphasizing appearance, not cell content.

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 intended use is implied by the listed formatting operations and the explicit statement that only passed properties are modified, but it never states when to choose this tool over alternatives such as xlide_manage_conditional_format or xlide_manage_sheet. There is no explicit exclusion or when-not-to-use guidance.

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