Format Cells

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

Annotations already indicate destructiveHint=true. The description adds concrete behavioral details: hazard-gating with allow_loss override, auto-backup, atomic verified save, and refusal while the file is open in Excel. These go beyond the annotations and inform the agent of safety and failure modes.

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?

The description is dense but organized: it starts with the core action, then enumerates parameter structures, then lists behavioral guarantees. Every sentence adds value, though it could be split into clearer subsections for readability.

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?

Given 11 parameters, no output schema, and a destructive annotation, the description covers the essential formatting object structures, safety behaviors, and the Excel-open refusal. Missing details on required parameters like path/location are minor, as they are common across siblings, but a fully complete description would address them.

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?

The schema provides no parameter descriptions (0% coverage). The description compensates by detailing the structure of number_format, font, fill, border, and alignment, including field names and hex color format. However, it leaves path, location, sheet, backup, allow_loss, and verify_com unexplained, so coverage is incomplete.

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?

Clearly states the action (apply formatting) and the target (a range), and explains the merging behavior that preserves unspecified attributes. This distinguishes it from data-writing tools like set_cell or write_range, making its purpose unambiguous.

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 description implies a formatting use case but does not explicitly contrast with alternative formatting tools (e.g., set_merge, set_dimensions). It mentions that named styles and conditional formats are a 'design pack,' hinting at limitations, but gives no direct when-to-use vs. 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.