update_field

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

With no annotations, the description must disclose behavioral traits. It only states 'Update one field', implying mutation, but does not mention side effects (e.g., whether other fields are affected), required permissions, or error behavior if the kind does not match. The constraint about kind matching is helpful but insufficient for full 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 extremely concise at one sentence. It is front-loaded with the core action. However, it sacrifices completeness for brevity, which slightly reduces its utility. It earns points for being succinct but loses a point for not covering essential details.

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?

Given the complexity of the tool (nested patch with discriminated union), no annotations, and schema coverage 0%, the description is incomplete. It fails to explain the purpose of the different patch types (radial vs uniform) or how to use them. The presence of an output schema is noted but not visible in the provided data, so it does not compensate.

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 should compensate. It adds meaning only for the 'patch' parameter by requiring its kind to match the existing field kind. No explanation is given for 'scene_name' or 'item_id', and the nested fields within patch (mode, center, etc.) are not described. The description adds minimal value beyond the schema.

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 'Update one field', which identifies the action and resource. The tool name 'update_field' is self-explanatory. However, it does not elaborate on what updating a field entails or differentiate from sibling update tools like update_object or update_action, but the resource type is implicit.

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 a key usage constraint: 'patch.kind must match its existing field kind.' This guides the agent on a critical prerequisite. However, it does not specify when to use this tool versus alternatives, such as when to update a field versus using add_field or apply_scene_patch. The guidance is minimal but relevant.

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