MCP Tool
nova.capture_app_screenshot
For visual evidence, screenshots, and reviewable differences, an agent uses this public tool to check the state or evidence for "App Screenshot Active-Target Guard". It explains which current signal can be used as evidence and when a follow-up step needs a fresh target check.
Canonical reference for a public MCP tool name.
- Type
- MCP tool
- Family
- Streaming & Screenshots (Advanced)
- Effect
- read-only
- Status
- Explained
- Path
- 31.11
Purpose
What this entry explains
What it does
nova.capture_app_screenshot
An agent uses this tool to check the state or evidence for "App Screenshot Active-Target Guard". It belongs to visual evidence, screenshots, and reviewable differences; agents should combine it with current discovery, target awareness, and the visible result.
Use when
- Use this entry when an agent needs to check the state or evidence for "App Screenshot Active-Target Guard" for visual evidence, screenshots, and reviewable differences.
- Use it to understand the public tool name, its expected boundary, and the response signals to check.
- Use it before chaining follow-up tools so the next step is based on current evidence.
Reference Use
How agents should cite and apply this area
Examples are maintained at family level and use only public tool names or reference paths already present in the catalog.
Family example
A user needs visual or media evidence in visual evidence, screenshots, and reviewable differences without capturing private content unnecessarily.
The agent starts with nova.stream_url, reads the current response or reference, and only then chooses the concrete next tool.
Capture only needed evidence, keep recording state visible, and respect private content.Contract
Inputs and important response fields
This page is a public reference. Agents and integrators should still read current MCP tool discovery before execution, because schemas can be gated by settings or version.
Inputs
agentId
Agent identity for claim, audit, or work context.
| Response field | Explanation |
|---|---|
reasonCode | Machine-readable reason for a warning, block, or special behavior. |
Safety
Boundary before execution
Reads current state or evidence. It should not be treated as permission to act without a fresh next-step check.
Use the response as current evidence, then choose a more specific next tool only after target, scope, and freshness are clear.
For humans, this entry explains what an agent reads in visual evidence, screenshots, and reviewable differences and which current signal should be checked before trusting the result.
High-Impact Review
Execution boundary and recheck hints
Review category: Recording/screenshots/media
Capture only the needed visual or media evidence and respect private content, recording state, and export boundary.
False assumption: screenshots or recordings contain only technical evidence.
Recording, screenshot, media access, or export must be visible to the user and purpose-bound.
Before capture, check target, scope, and privacy; use artifacts as evidence only and do not forward them unrequested.
Abort if private content is visible, media permission is unclear, or the export contains more than needed.
Safety Axes
How this path can affect work
Axes are stable catalog signals for humans, agents, and LLM discovery. One path can carry several axes.
read_current_state
Reads current state, response signals, or evidence without treating that alone as permission for a follow-up action.
Use the signal as current evidence and re-check target, scope, and visible state before any follow-up action.browser_state_change
Changes tab, navigation, focus, claim, scroll position, window state, or browser environment.
Confirm the target context visibly before execution and verify that the expected browser state was reached afterwards.recording_or_media
Creates or reads screenshots, recordings, media, visual evidence, or audio/video signals.
Capture only needed evidence, respect private content, and keep media or recording state visible.