get_font_variation_axes

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

With no annotations, the description carries the full burden and largely delivers: it discloses the platform prerequisite (Figma Desktop with Plugin API Update 138 for variable fonts) and the two possible result shapes (axis list vs. null/variable:false). It does not describe the axis objects' internal fields (e.g. min/max/default), which leaves a modest gap for a read tool with no output schema.

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?

Two tightly packed sentences: the first front-loads what is returned including edge cases, the second covers usage and prerequisites. Zero filler and every clause earns its place.

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 one-parameter read tool with no output schema, the description adequately explains the return (axes or null/variable:false) and the environment requirement. It stops short of detailing the axis payload structure, which is the only thing an agent might still want to know.

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% and the single 'family' parameter is documented in the schema with an example ('Inter'). The description adds no syntax or format detail beyond what the schema already provides, so the baseline 3 applies.

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 (Return) and resource (the OpenType variation axes a font family exposes), gives concrete examples (wght, slnt, opsz), and covers the static-family case (null/variable:false). An agent can distinguish this from sibling text/style tools without opening the schema.

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?

Explicitly states when to use it — 'Use this before setting variationSettings on create_text / set_text_style / create_text_style' — naming the exact downstream tools it precedes. No inference required about timing or purpose relative to alternatives.

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