open_document

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

Annotations already declare non-read-only, non-destructive, non-idempotent, and local (openWorldHint=false). The description adds one genuinely useful behavioral fact: foreign CAD formats are imported into a new document rather than opened in place, which explains a side effect. It remains silent on what happens to currently open documents, whether the operation can fail on a missing/invalid path, and what `activate` actually does.

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?

A single front-loaded sentence that names the primary format first and the import cases second. Every clause carries information; nothing is padded or restated from the title.

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?

Incorrect — recalibrating: an output schema exists so return values need no explanation, but the definition still leaves the `activate` flag and the effect on existing documents unspecified for a state-changing open/import operation.

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 carries the full burden, and it says nothing about either parameter. `path` is obvious from its name but `activate` (boolean, default true) is entirely unexplained — an agent cannot tell whether it controls window focus, document switching, or the active document in the session.

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?

States a specific verb ('Open') plus the exact resource ('a `.FCStd` file'), and clarifies the import variant for STEP/IGES files. It is clearly distinguishable from create_document or save_document by the word 'open', though it never names a sibling explicitly.

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?

Usage is only implied: an agent infers this is the entry point for working with an existing file, and the parenthetical usefully clarifies that non-native formats are imported into a new document. There is no explicit statement of when to prefer it over create_document, or of preconditions such as the file existing or documents already being open.

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