stop_interactive_viewer

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

With no annotations, the description must disclose behavioral constraints on its own. It usefully restricts the operation to standalone viewers owned by the MCP process, preventing agents from attempting to close external viewers. Yet it does not describe error behavior for unknown or already-closed viewer IDs, whether closing is idempotent, or what result is returned.

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 entire description is one front-loaded sentence that states the action and its scope without filler. Every word earns its place; no unnecessary details are included.

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 one-parameter close operation this is minimally adequate, especially because 'owned by this MCP process' clarifies the applicable viewer set. However, with no output schema and no annotations, the description leaves the agent without guidance on return values, failure modes, or prerequisite checks such as verifying viewer status first.

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?

The schema provides only a required 'viewer_id' string with no description (0% schema description coverage). The description does not mention viewer_id at all, leaving the agent to infer from the parameter name and tool name that it identifies the viewer to close; it does not explain where to obtain it or any expected format.

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 uses a specific verb, 'Close,' and identifies the exact resource: 'a standalone MoonRay viewer owned by this MCP process.' This clearly separates the tool from sibling tools such as launch_interactive_viewer, set_interactive_viewer_exposure, and capture_interactive_viewer_snapshot, which perform different operations on the same resource type.

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 phrase 'owned by this MCP process' implies the tool is for closing viewers that this process launched, giving some context. However, it does not explicitly state when to prefer this over alternatives, how to confirm a viewer is owned by the process, or what to do if the viewer is already closed.

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