spacing_edit

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

The description discloses key behavioral details: operations are applied atomically, and adjusting bearings can move outlines while advances do not. However, it does not mention revision checks, validation failures, or other side effects like potential destructive changes.

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 well-structured, using two short sentences to convey core purpose and a key behavioral nuance without unnecessary detail.

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 description names the supported operation types and a key side effect, which is helpful. However, it lacks guidance on parameter usage and expected revision handling, making it only partially complete for a tool with a complex operations union.

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 provides no explanation of the parameters, including project_id, expected_revision, operations, or the operation discriminators. With 0% schema description coverage, the description leaves all parameter semantics to the schema.

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 tool's purpose: atomically setting advances, side bearings, kerning groups, or pairs. It names the specific spacing resources and adds a useful distinction between bearings and advances.

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 does not explain when to use this tool versus alternatives like glyph_edit or font_update, and it does not mention concurrency controls such as expected_revision. The atomicity hint is useful but not sufficient as usage guidance.

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