Inspect as text

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

No annotations are supplied, so the description carries the full behavioral burden. It does disclose the shape of the output (ASCII grid + legend + color histogram) and implies a non-mutating read, but says nothing about cost, size limits, or what happens when the requested frame/layer does not exist.

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?

Two short sentences with zero filler, front-loading what is returned before the usage rationale. Nothing could be removed without losing 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?

There is no output schema, so the description must convey return content, and it does so at a useful level (grid, legend, histogram). The remaining gap is minor: the undocumented maxWidth parameter and the absence of any note on resolution/truncation behavior for large frames.

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 75%, so the schema already explains frame, layer and project defaults. The description adds no parameter meaning at all, and maxWidth — the one parameter with no schema description — is left completely unexplained (no mention that it caps grid width).

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 concrete verb and return artifact: return the frame as an ASCII grid, legend and color histogram, and scopes it to a single frame. That is enough to tell it apart from image-returning siblings, but it never names the sibling (sprite_preview) that an agent would otherwise reach for.

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?

Gives a clear use context: text-only reasoning, and iterating on one frame without vision. It implies the alternative (vision-based preview) but does not name it or state when this tool should not be used, so it stops short of explicit routing.

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