Inspect Three.js scene objects by selection: the cursor becomes a crosshair, prompting the user to pick an object in the 3D view and returning it.
[INSPECT] Read-only. Click-to-inspect: the cursor becomes a crosshair — tell the user to click an object in the 3D view. Returns that object.
| Name | Required | Description | Default |
|---|---|---|---|
| timeout | No | Max wait in seconds (default: 15, max: 60) |
Changes observed during successful MCP inspections.
v0.5.0Input schema / additionalPropertiesRemoved value: -falsev0.4.1Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, but the description adds non-trivial context the annotations cannot: this tool blocks on real user interaction, changes the cursor to a crosshair, and therefore requires the agent to prompt the user. That is material behavioral knowledge for an agent orchestrating the call.
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?
Two short sentences, front-loaded with the [INSPECT] Read-only tag and the core behavior. Zero filler; every clause carries an instruction or a constraint.
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?
With no output schema, the description does state the return ('Returns that object'), the interaction model, and the safety tag, and the timeout semantics live in the schema. It stops short of saying what happens if no click arrives before the timeout, which is the one remaining gap for an interactive, blocking tool.
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?
Single optional 'timeout' parameter with 100% schema description coverage (default 15s, max 60s), so the schema fully carries parameter meaning. The description adds nothing about the timeout or what a timeout yields, which is the correct baseline when the schema does the work.
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 and resource ('Click-to-inspect ... Returns that object') and makes the interactive mechanism explicit via the cursor-to-crosshair detail, which sets it apart from programmatic pickers like raycast. It does not name that sibling directly, so the differentiation is implied rather than spelled out.
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?
'Tell the user to click an object in the 3D view' gives an operational procedure but no when-to-use framing against alternatives such as raycast or object_details, and no conditions under which this is the wrong tool. Usage is implied by the click flow rather than stated as guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.