Drawing: Apply Drafting Standard

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

With only readOnlyHint=false available in annotations, the description carries the burden well and discloses non-obvious behavior: idempotency ('a second call reports nothing'), non-destructive reuse of existing ISO-25/ANSI styles rather than reset, per-item created/already-present reporting, and atomicity ('refuses ... before any write'). It also propagates the underlying style-tool refusal semantics, which an agent cannot infer from the schema.

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 behavior and then the reporting/refusal semantics; most sentences earn their place. The trailing 'In the `lean` profile (Task 13)' is an opaque internal reference that adds no actionable information and slightly dilutes the close.

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 three-parameter, mutating tool with an output schema, the description covers what changes, idempotency, atomicity, and failure modes, so return values need no explanation. The unexplained 'lean profile (Task 13)' reference and the absence of guidance against the standard/layer sibling tools are the only notable gaps.

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 all three parameters are already documented with concrete values (INSUNITS mm, LTSCALE 1, ISO 128 lineweights, iso/ansi values), establishing a baseline of 3. The description adds only marginal extra meaning — that the mech layer naming is shared across standards — which is useful rationale but not new invocation syntax.

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 and resource ('apply drafting standard') and enumerates exactly what gets set: dimension style, text style, shared units, and optionally the mech layer set. An agent can distinguish it from the granular siblings dimstyle_create/textstyle_create/dimstyle_set_current because the description explicitly frames it as the bundled 'one call for the common case'.

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?

Explicitly frames the intended use ('one call for the common case') and names an alternative for a related need ('use dimstyle_modify to change one'), plus an explicit refusal path for unknown standards. It does not, however, differentiate from close siblings that also bootstrap standards/layers, such as drawing_apply_iso_layers or template_apply_layers, so routing against those is left to inference.

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