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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description contributes the content scope of the result (custom plus safe system fonts), but says nothing about ordering, whether custom fonts require a project context, or the shape of each entry.

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?

One short fragment with no filler, and the usable-in context comes before the font taxonomy. It is efficient, though the sentence fragment style leaves the action itself (listing/returning) implicit rather than stated.

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 simple read-only list tool with zero required parameters and full annotations, the description covers what is returned at a category level. It stops short of describing the result entries (names, identifiers, how to reference a font in add_text) that would make it fully self-sufficient given there is no output schema.

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% for the single optional projectId parameter, so the schema already explains the default-to-open-project behavior. The description adds no meaning beyond that, which is the expected baseline for a one-parameter tool whose schema is fully annotated.

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 names the resource (fonts) and scopes it precisely to captions, text and overlays, then splits it into two categories: custom (Google/uploaded) and safe system fonts. It is a noun phrase rather than a verb+resource statement, and it never contrasts itself with font-related siblings such as add_google_font, create_font_upload or remove_font, but the returned set is unambiguous.

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 when-to-use guidance at all. The description does not say this is the discovery step before add_google_font / create_font_upload / remove_font, does not mention that projectId defaults to the open project, and gives no exclusions or prerequisites.

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