Add Shape Modifier

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

Annotations already declare this is a non-read-only, non-destructive mutation, so the safety burden is partly covered. The description adds useful context about the returned modifier path/property names and their relation to set_keyframes, but does not explain side effects, existing modifier behavior, or failure conditions.

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?

The description is front-loaded, compact, and every sentence contributes: operation scope, parameter mapping/default, and return usage. There is no redundant or filler text.

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 mutation tool with nested params and no output schema, the description covers the core operation and return values reasonably well. However, it leaves layer_id semantics and some behavioral details underspecified given the 0% schema description coverage.

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 0%, so the description must carry parameter meaning. It adds useful semantics for params, group_index default (1), and the modifier choices, but layer_id is never explained and nested params behavior remains only briefly described.

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 states a specific verb and resource: adding trim_paths, repeater, or round_corners to a shape group. It is clear enough to distinguish this from general property/effect tools, though it does not explicitly name a sibling alternative.

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?

The description implies usage by saying the return values are for set_keyframes, but it does not explicitly say when to choose this tool versus add_property or other shape-related tools. Guidance is present but 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.