set_font_color_rules

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

With no annotations, the description carries full burden. It discloses key behavior: discrete bands, interval semantics [min, max), and scope (measure column in table/matrix). It does not mention overwrite behavior or how to clear rules, but the core effect is clear.

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 three sentences, front-loaded with the main purpose, and every sentence provides distinct value: purpose, sibling differentiation, and rule format. No unnecessary words 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?

Given no output schema and no annotations, the description is quite complete: it explains the operation, target, rule format, and interval behavior. It does not cover edge cases like overlapping rules or error handling, but those are not essential for basic invocation.

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 high (83%), and the description adds important meaning to the 'rules' parameter by explaining the [min, max) interval behavior and the JSON structure. This goes beyond the schema's brief description, making the parameter semantics clearer.

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 states a specific action ('Apply DISCRETE rule-based FONT-COLOUR bands') with a clear target ('measure column in a table/matrix'). It distinguishes itself from the sibling tool set_conditional_formatting by explicitly noting it applies to text colour instead of background.

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 clearly implies usage for font-color formatting by referencing the same rule structure as set_conditional_formatting but for text colour. It gives a comparative alternative but does not explicitly state when not to use it or list other alternatives like gradient color or icon rules.

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