set_run_font

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

With no annotations, the description must disclose behavioral traits. It only states the action without mentioning side effects, error conditions (e.g., invalid run index), or validation of font names. The presence of an output schema is noted but not used for behavioral context.

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 concise and front-loads the purpose. The argument list is clear but somewhat informal; it could be more structured as proper parameter descriptions but contains no fluff.

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?

The tool is simple, but the description omits important context such as preconditions (e.g., the paragraph must exist and contain runs), what happens on invalid input, and return value information despite the presence of an output schema.

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 description adds basic meaning beyond the schema titles: it clarifies para_id as 'paraId of the target paragraph', run_idx as 'zero-based index', and gives examples for font_name. However, it lacks constraints or allowed values, and schema coverage is 0%, so the description partially compensates.

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 clearly states the action: set the font of a specific run, including that the run index is zero-based. It uses a specific verb and resource, but does not explicitly distinguish among similar siblings like set_run_color or set_run_size.

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 guidance is provided on when to use this tool versus alternatives (e.g., other set_run_* tools). The description only lists arguments without context for selection.

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