get_font_info

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

With no annotations, the description carries the full burden. It says 'Get information' which signals a read-only operation, and it lists what it returns. It does not disclose potential failure modes (e.g., no open font) or explicitly state it is non-mutating, but for a simple getter, this is adequate. There is no contradiction with annotations (none provided).

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 compact: one sentence for the purpose, a second listing the returned data. It is front-loaded and contains no redundant words. Every sentence 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 zero-parameter, read-only query tool, the description is complete. It enumerates all the information the tool returns (family name, units per em, glyph count, masters, axes, metrics, instances), which fully informs the agent what to expect. Without an output schema, this is sufficient.

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 tool has zero parameters, so the baseline is 4. The description naturally has nothing to add about parameter semantics, and the schema coverage is 100% (vacuously). No further explanation is needed.

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: 'Get information about the currently open font in GlyphsApp.' It specifies the resource (font) and the action (get info), and it distinguishes itself from siblings like get_masters or list_glyphs by focusing on aggregated font data rather than specific subsets.

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 gives clear context by specifying 'currently open font,' implying it is used to inspect the active font. It does not explicitly mention alternatives or when not to use it, but among many sibling getters, it implicitly serves as the general overview tool. No exclusions are stated, but the scope is unambiguous.

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