Manage conditional formatting

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

Even though annotations already indicate destructive and non-read-only behavior, the description adds meaningful operational detail: first-match-wins evaluation, highest-priority default index 0, update replacing the ENTIRE rule, and index shifting after mutations. This goes well beyond what annotations or schema express.

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 every sentence earns its place. It front-loads the core addressing model, then systematically covers add/update/delete semantics without filler or repetition.

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 complex 11-parameter mutation tool with no output schema, the description covers addressing, state sourcing, side effects, action-specific requirements, condition types, formula usage, and required format fields. Nothing essential for correct invocation is missing.

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%, but the description still adds significant semantic value by specifying action-dependent requirements: add needs ranges, condition_type, condition_values, and at least one format field; update/delete require sheet_id + index; CUSTOM_FORMULA needs a '=...' formula; index defaults to 0 for add. This is a strong enhancement over raw 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: 'Manages conditional-format rules that style cells when a condition holds.' It immediately scopes the tool to boolean rules and explicitly routes gradient color scales to raw_request, distinguishing it from siblings.

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 gives concrete usage context: rules are addressed by sheet + index, current rules are read from get_spreadsheet, and indexes must be re-read after every mutation because add/delete shift later indexes. It also names raw_request as the alternative for gradient color scales, providing clear routing.

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