set_glyph_width

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only says 'Set', implying mutation, but does not state whether the change is permanent, affects all masters or just the one in master_id, or whether width is in font units. For a mutation tool, this is insufficient.

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 a single, clear, front-loaded sentence with no fluff. It is appropriately short for its purpose, but it is unhelpfully under-specified, which slightly lowers the score from a perfect 5.

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 has 3 parameters, no output schema, and no annotations. A minimal description of 'set advance width' is not enough for an agent to know what width means, how master_id is used, or whether the operation has side effects. The description is far from complete for a real-world glyph-editing action.

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 0%, so the description must compensate, but it mentions none of the parameters. Width units, glyph_name format, and master_id semantics are entirely unaddressed. The description adds no value beyond what the parameter names trivially imply.

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 verb ('Set'), a specific resource ('advance width of a glyph'), and clearly distinguishes this from sibling tools like set_glyph_color, set_glyph_unicode, or set_kerning_pair. An agent can immediately tell what property is being modified 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?

There is no guidance on when to use this tool versus alternatives, no mention of prerequisites (e.g., current font loaded), and no exclusion of cases like when kerning pairs or other spacing adjustments are more appropriate. The agent is left to infer context entirely.

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