.cube LUT

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

Annotations cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description adds behavior beyond them: the header carries measured deviation vs the direct conversion, and pure per-channel transfers auto-emit 1D instead of 3D. It omits error behavior and precision details, but disclosing the conditional 1D emission and the size ceiling is meaningful added context.

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 tight sentences: purpose first, then the output/behavioral nuances, then the size constraint and its alternative. Every clause carries information and nothing is repeated from the schema or annotations.

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 no output schema, the description partially covers the return by describing the LUT header containing measured deviation, implying file text is emitted. It does not state the concrete return shape (raw text, path, or attachment), which is the one thing an agent still has to guess.

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 from/to/size are already fully documented with examples and bounds. The description adds only marginal semantics — the rationale for the 33 cap and where to go for larger sizes — which is a slight plus over the baseline of 3 rather than a substantive enrichment.

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+resource ('Render a conversion as a .cube LUT file') and names the consumer ecosystem (Resolve, Premiere, Final Cut, OBS, ffmpeg), which immediately separates it from siblings like shader, icc, css, and code.

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 an explicit exclusion — 'Size ≤ 33 here (larger via the library or https://color-space.io/)' — routing the agent away for oversized LUTs. It does not, however, contrast this tool against siblings such as shader or icc for non-LUT export formats, so the when-to-use picture is clear but not complete.

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