partdesign_fillet

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

With no annotations, the description carries the full behavioral burden and does so: it discloses the pre-handle validation (isValid, solid count, bounding-box growth), the failure semantics (feature removed, Body Tip restored, BlendCheckFailed naming offending edges), and the partial-result behavior of allow_partial. It even documents the return payload and the edge-subset warning case.

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 core action and parameter syntax before the validation rationale. The r=0.6/15%-larger anecdote and issue #283 reference are mildly digressive but serve to justify the validation behavior, so the length is mostly earned.

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 6-parameter mutation tool with no output schema and no annotations, the description supplies parameter formats, validation scope, success payload, and failure/exception behavior. Nothing an agent needs to invoke it correctly appears 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 coverage is 0%, so the description must compensate, and it explains edges (e_* tags or 'EdgeN' index strings), radius (mm, must be > 0), per_edge (validate after each edge), and allow_partial (off by default). Only the required 'feature' parameter and 'name' are left unexplained, a modest gap against otherwise strong coverage.

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 (Fillet) and resource (edges of a feature in a Body) plus the workbench context (PartDesign), which is enough to separate it from the generic fillet_edges sibling. It stops short of explicitly contrasting scope with fillet_edges, leaving the PartDesign-vs-Part distinction to be inferred from the parenthetical reference.

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?

Mentions fillet_edges and that the same validation applies, implying this is the PartDesign-body variant, but never gives an explicit 'use this instead of X when...' rule. The per_edge and allow_partial flags hint at workflow choices without stating when each mode is preferred.

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