vroid_find_button

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

With no annotations provided, the description fully carries the burden of behavioral disclosure. It reveals the matching mechanism (button chrome), the output ordering (biggest-first, image px), and the semantic meaning of a disabled grey pill, including the specific validation context on the VRM Settings modal. This goes well beyond the schema and gives agents critical operational knowledge.

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 a compact three sentences, each earning its place: purpose and differentiation (sentence 1), technical rationale and output format (sentence 2), and practical interpretation of a key signal (sentence 3). It is front-loaded with the core purpose and contains no filler, making it highly efficient for agent parsing.

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?

The tool is moderately complex with 4 parameters and an output schema, but the description covers the essential context: why this tool exists (OCR failure), how results are returned (blobs, ordered), and what a specific result indicates (disabled state). Combined with the exhaustive schema descriptions, nothing critical for correct invocation 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?

Schema description coverage is 100%, so the baseline is 3. The description adds little beyond what the schema already explains (e.g., the color enum semantics are already in the schema). It does reinforce the color meanings but does not add new parameter-level detail for label, limit, or region. The description therefore does not elevate above the baseline.

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: finding VRoid buttons by color rather than text. It specifies the resource (primary action buttons), the method (color matching), and explicitly differentiates from text-based approaches. The mention of 'ready for vroid_click' also clarifies the intended downstream use, making the tool's role unambiguous relative to siblings like vroid_find_text.

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 provides strong usage context by explaining why color-based matching is necessary (tesseract loses white labels), implicitly steering agents away from text-based tools. It also gives guidance on interpreting results (grey pill means disabled) and notes the typical next step (click). However, it does not explicitly name alternative tools or enumerate when NOT to use this tool, which keeps it from a 5.

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