project_painting_write

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

With no annotations, the description carries the full burden and does well: it discloses that output goes to a NEW 3MF (not in-place), that other channels/topology are preserved, that a SHA is required (optimistic concurrency), and that the change affects all uses of the mesh. It omits permissions and any failure/validation behavior, but the core mutation profile is clear.

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-loaded with the core action, then structured breakdowns for kind and change shape. The terse, fragmentary phrasing is efficient and every clause carries information, though the telegraphic style slightly reduces readability.

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 7-parameter mutation with no annotations and 0% schema coverage, the description supplies the critical semantics (write-to-new-file, SHA guard, change encoding, side-effect scope). An output schema covers return values. Remaining minor gaps are the exact roles of source vs destination and member defaults.

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 0%, so the description must compensate, and it explains the hardest parameters well: kind values (support/seam/material/fuzzy_skin) and the changes structure (0-based triangle plus state 0/1/2 or material 1..16, or mask with null-clears semantics). source/destination/object_id/member/expected_source_sha256 are only implied by name and the 'inspect ... first' hint, leaving some gaps.

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 (paint) and resource (explicit triangles in a NEW 3MF) with a clear scope constraint ('preserving other channels and topology'). It implicitly contrasts with the read sibling project_painting_read via the 'inspect ... first' workflow, though it doesn't name that tool explicitly.

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?

'Inspect member/object IDs and SHA first' establishes a prerequisite workflow that points to the read counterpart. 'Affects all uses of that mesh' warns of the blast radius. It lacks an explicit when-not or a named alternative, keeping it below 5.

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