Lock Viewport

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

Annotations provide only a title, so the description bears full responsibility for behavioral transparency. It discloses that the tool toggles a viewport's display scale lock but does not mention side effects (e.g., preserving current scale, preventing scale edits), reversibility, or required permissions. For a state-changing operation, this is minimal.

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 a single, front-loaded sentence that directly states the purpose. 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?

The tool is simple with only two well-documented parameters and an output schema, so minimal description is needed. The description covers the core action, though it could mention the effect of locking (e.g., prevents display scale changes) and that a handle comes from viewport_list (already in schema). Overall, it's sufficient for a simple toggle.

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 100%, with both 'handle' and 'locked' having clear descriptions. The tool description adds little beyond the schema, but it aligns with the schema's semantics. Since the schema fully documents parameters, baseline 3 is appropriate.

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 'Lock or unlock a viewport's display scale,' naming the exact resource (viewport's display scale) and the action (lock/unlock). This distinguishes it from sibling tools like viewport_set_scale, which changes the scale rather than locking it.

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?

No guidance is given on when to use this tool versus alternatives. Notably, sibling viewport_set_scale exists for changing scale, but the description does not mention it or state that this tool is for preventing scale changes. Users must infer usage from the name/description alone.

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