オブジェクトの編集

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

With no annotations, the description carries the full burden, but it only discloses the merge-update behavior for params and the source of object_index. It does not mention side effects, reversibility, permissions, or error conditions, which are particularly relevant for a mutation tool. The merge behavior is already partially stated in the schema, so the description adds limited extra transparency.

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 compact at two sentences, front-loads the primary action, and adds only essential clarifications about object_index and effect_index. Every phrase is useful, and it neither repeats schema information nor wastes words.

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 complex tool with 10 parameters, no annotations, and no output schema, the description is too terse. It covers the core action but omits critical context such as return values, behavior for edge cases (e.g., invalid indexes, deletion restrictions), and relationships with related tools. The description does not give an agent enough to safely invoke the tool in all scenarios.

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 only 40%, so the description should compensate, but it only directly explains object_index (from read_project) and effect_index ('specify to merge-update its params'). It hints at layer/frame range via 'レイヤー/フレーム範囲' but does not detail the individual parameters like layer, frame_start, frame_end, or path. The merge behavior is also already in the schema, so added value is moderate.

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 clearly states the verb (変更する, to modify) and the resource (既存オブジェクト, existing object), and lists the specific aspects being modified (layer/frame range/effect parameters). It distinguishes the tool from siblings like delete_object and add_objects by focusing on editing an existing object.

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 provides clear context: it is for modifying existing objects, implying it should be used after reading a project (object_index from read_project). However, it does not explicitly name alternative tools or state when not to use this tool, so it falls short of a full 5.

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