compare_proportions

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

With no annotations, the description carries the behavioral burden. It explicitly discloses side effects: 'Does not modify glyph colors by default' and what happens when mark_glyphs=True. It also surfaces default scope behaviors that are not visible from the schema alone.

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 well-structured and front-loaded with the core purpose. The recipe note, numbered checks, defaults, and side-effect disclosure each earn their place, and bullet-like formatting keeps it scannable.

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 moderately complex comparison tool with no annotations, the description covers scope, defaults, side effects, and the exact categories being checked. Since an output schema exists, return-value details are not required in the description.

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, and it does. All three parameters are explained with defaults and conditions: glyph_names, master_id (empty means all masters), and mark_glyphs (only colors when explicitly requested). This adds real meaning beyond the bare input 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?

States a specific verb and resource: 'Compare width proportions across glyphs within a font.' It then enumerates three concrete check categories, which clearly distinguishes it from sibling tools like compare_stems or check_related_forms even though they are not named.

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?

Provides clear context by pointing to get_recipe('audit_consistency') for a full audit, implying this tool is for targeted proportion checks. It also specifies default behavior for missing glyph_names and master_id, giving an agent practical invocation guidance.

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