sheets_format_cells

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

Annotations already declare readOnly=false, idempotent=true, and destructive=false, so the safety profile is covered. The description adds no behavioral context beyond the annotations: it does not say whether existing formatting is replaced or merged, whether cell contents are preserved, or what is returned.

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?

A single, front-loaded sentence that wastes no words. It is efficient, though it is perhaps too terse to convey the tool's full behavior.

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 idempotent mutation whose safety annotations and full schema coverage carry most of the load, the description is adequate. However, it omits whether content is altered vs. presentation only and how it relates to overlapping siblings, leaving a small gap for a 3-parameter tool with a nested object.

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 and nested format property is already documented in the schema. The description's mention of 'font, color, alignment, and number format options' loosely mirrors those properties but adds no syntax or format detail 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 ('Formats') and resource ('cells in a range') and enumerates the formatting dimensions (font, color, alignment, number format). It is clearly distinct from read/write siblings, though it never names which sibling handles overlapping concerns like conditional formatting.

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?

No when-to-use guidance is present. It does not clarify how this differs from sheets_add_conditional_formatting or sheets_write_range, nor whether it preserves cell values while only altering presentation. The agent must infer usage entirely.

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