Open Document

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

With no annotations present, the description carries the disclosure burden. It reveals the load-as-new-document behavior, the default focus switch, and the refusal when `make_active:false` would cause destruction of a blank document. It does not fully explain what happens to other open documents, but the central side-effect behavior is covered.

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 short and front-loaded with the core purpose. However, the comparison with `import_scene` is stated twice ('Unlike `import_scene`' and 'Differs from `import_scene`'), which is slightly redundant and could be tightened.

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 simple two-parameter, no-output-schema tool, the description covers the core purpose, the distinguishing behavior, parameter defaults, and an important edge case. It is complete enough for selection and invocation, though it omits details about file format support or return behavior, which are not essential here.

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 the schema already documents both parameters well. The description adds minimal extra semantic value, mainly reinforcing the default and purpose of `make_active` and the contrast with import. This meets the baseline for well-covered schemas.

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 a specific action and resource: 'Load a Cinema 4D scene file as a new document.' It explicitly distinguishes this tool from `import_scene`, so an agent can tell them apart based purely on the description.

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 gives direct usage guidance by contrasting with `import_scene`: use `open_document` when you need the file as its own document, not merged into the current one. It also explains the behavior of the `make_active` parameter and the rejection condition, which is strong invocational guidance.

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