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

Annotations only declare readOnlyHint=true; the description adds two facts the annotation does not carry: "nothing is charged" and that the payload may come live, from cache, or from a stale snapshot when Higgsfield does not answer. That freshness caveat is genuinely useful behavioral disclosure. It stops short of describing ordering or failure modes if the upstream never responds.

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?

Three short lines, front-loaded with the free/read-only fact and the downstream routing. The final sentence ("source says live, cache or fallback (our snapshot when Higgsfield did not answer)") is slightly telegraphic, but every sentence carries real information.

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 parameterless read tool with an output schema, this covers everything an agent needs: what it returns, that it costs nothing, how to use the result in the surrounding workflow, and how reliable the data is. Nothing material is missing.

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 takes zero parameters, so the baseline is 4 and there is nothing for the description to disambiguate on the input side. The description instead documents the result fields (id, name, name_ru, preview_url), which is helpful but redundant with the existing output 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 ("List the visual styles Higgsfield Genjutsu Restyle can apply") and immediately distinguishes itself from the sibling generation tools by noting it is a free lookup. An agent can tell exactly what it gets 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?

Explicitly routes the agent forward: "Pass the chosen id as preset_id to estimate_higgsfield_restyle / create_higgsfield_restyle" clearly positions this as the prerequisite step for those two siblings. It does not state a when-not case, but there is no competing alternative tool for this lookup, so the gap is minor.

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