create_sketch

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

With no annotations, the description carries the full burden and does so well: it discloses three side effects (writes to disk, auto-creates an in-memory workspace, opens an interactive browser preview), states the directory is auto-created, and warns that the resulting file has no OS association so it shouldn't be handed to the user. It omits failure/overwrite behavior when a file already exists at the target path, which is the main gap for a write tool.

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?

Front-loads the action before any caveats, then layers side effects, path convention, the "don't show the file" warning, and the component rule in a tight, scannable sequence. Every sentence changes what an agent would do; the only mild overlap is restating the default path already present in the schema.

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 21-parameter write tool with no annotations and no output schema, this covers what matters: side effects, where the file lands, how to skip preview/capture, and the non-obvious component policy that would otherwise cause agents to inline utility code. The absence of output-schema info is acceptable since the description flags the inline screenshot returned by capture:true.

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 the baseline is 3, but the description adds genuine semantic value beyond the schema: declare PRNG/noise/easing/color/vector helpers as components rather than inlining them, use list_components to enumerate them, and use mulberry32/fbm2D exports directly. It also restates the default path convention and preview default, which the schema already covers.

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 first sentence names a specific verb and resource ("Create a new .genart sketch file") and enumerates the three input families (metadata, parameters, algorithm), immediately distinguishing it from save_sketch/update_sketch/fork_sketch by the word "new". It does not explicitly name those siblings or state the boundary (e.g. use save_sketch to persist edits to an existing file), which keeps it short of a 5.

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 real routing guidance: use list_components to discover dependencies, set capture:true to avoid a separate capture_screenshot call, set preview:false to skip the browser, and don't present the .genart file to the user. It never says when to prefer this over save_sketch or update_sketch, so the sibling-selection rule is inferred rather than stated.

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