Image & Chart Prompt Assistant

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

No annotations are provided, so the description carries the full burden. It clearly frames the tool as advice-giver ('Get expert prompt templates and guidance'), implying a read-only, non-destructive assistant. It does not disclose any hidden side effects or special behaviors, but for a guidance tool, this is minimal risk. No contradictions with annotations exist since none are present.

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 two sentences, tightly packed with useful information. It front-loads the primary purpose, lists covered domains, and ends with a targeted usage note. Every sentence earns its place; no fluff or repetition.

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?

With 7 parameters (5 enums) and no output schema, the description covers the core functionality and highlights the chart_design+color_scheme combination. It doesn't elaborate on every request_type, but the enum in the schema provides that list, and the description gives sufficient context for the most common branching scenario. It could mention that it also handles prompt optimization/troubleshooting, but the schema implies it via the request_type enum.

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 coverage is 100%, so baseline is 3. The description adds a valuable cross-parameter hint: combining chart_design (request_type) with color_scheme yields a professional design system prompt. This enriches understanding beyond the schema's isolated parameter descriptions. It does not explain each parameter in depth, but the schema already does that adequately.

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 it provides 'expert prompt templates and guidance for Gemini image generation' and lists specific areas (photography, charts, lighting, etc.). It distinguishes itself from siblings like generate_image by focusing on guidance rather than generation, and explicitly mentions chart_design for chart-specific needs.

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 includes an explicit usage hint for charts: 'For charts: use chart_design with a color_scheme to get a full professional design system prompt.' It doesn't enumerate when not to use it or list alternatives, but this guidance covers a key use case. Context for other request types is implied through the enum in the schema.

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