open_file

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

With no annotations, the description carries the full burden of behavioral disclosure. It explicitly reveals the important stateful side effect of setting the working file, and it discloses that the return value matches get_basic_info. It does not mention persistence, permissions, or cancellation semantics, but the key behavioral trait is clearly stated.

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?

Three concise sentences, each serving a distinct purpose: the primary action, the stateful side effect, and the return value. There is no filler or redundancy.

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 tool with no output schema, the description covers the input formats, page behavior, stateful consequence, and return value by referencing get_basic_info. The only minor omission is a more exact return shape, but the reference to get_basic_info is acceptable.

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 input schema already documents fileId formats (bare ID, /file/<id> route, full URL) and pageId behavior. The description adds no new semantic detail beyond restating ID/URL and page selection, so it earns the baseline.

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 action and resource: 'Open a Paper file by its ID or URL, optionally at a specific page.' It also distinguishes itself from get_basic_info by noting the stateful side effect of targeting subsequent calls, which makes its unique role clear among the large sibling toolset.

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 clearly signals the intended use case by explaining that after calling it, subsequent calls without fileId will target this file. It does not explicitly state when to avoid it (e.g., preferring get_basic_info for one-off reads), but the behavioral context is strong enough to guide selection.

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