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

Annotations already declare destructiveHint=true, readOnlyHint=false, and openWorldHint=false, so the safety profile is covered structurally, and the description adds real context: patch semantics for non-None params, ML-to-agent source promotion with confidence=1.0, immediate persistence, review-receipt invalidation on geometry changes, and template isolation unless save_template is called. It also discloses the error return shape for a missing field_id. However the destructiveHint=true annotation is never reconciled in prose -- the description presents this as a routine patch without warning that a field's geometry or type can be irreversibly altered, which is the one behavior an agent most needs spelled out for a destructive operation.

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 organized under labeled blocks (Overwrite/merge, Persistence & review impact, When to use) that let an agent scan to the relevant concern. It runs long for a single-field update, and the parameter list is enumerated twice (in the header sentence and again in the patch paragraph), which is mild redundancy.

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?

An output schema exists, so return values needn't be described, yet the description still notes the updated-field dict and the error variant. With ten parameters, a destructive mutation, and cross-cutting effects on review receipts and templates, every consequence an agent needs before calling is present.

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% and each parameter already documents its range and None semantics, so the baseline is 3. The description earns above baseline by stating the unifying rule that ties all eight optional params together -- only non-None values overwrite, everything else is preserved -- which is a cross-parameter contract the per-field schema text cannot express, plus the conditional side effect on source/confidence tied to field_type edits.

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 description opens with a specific verb and resource plus the full attribute set that can be modified ('position, size, semantic name, type, or alignment'), and scopes it to 'the active workspace'. It is immediately distinguishable from add_field, remove_field, and update_fields, all of which are named with their own trigger conditions.

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?

A dedicated 'When to use' block states the single-field case explicitly and routes three alternatives: update_fields for 2+ fields in one call, add_field for missing fields, remove_field for false positives. Both the inclusion condition and the exclusion conditions are given, leaving nothing to inference.

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