Non-coverage contract

What HOL Guard does not claim to cover

Guard coverage is harness-, version-, and event-specific. This page makes fail-open behavior and observable blind spots first-class public facts instead of allowing “supported” to imply universal protection.

See the full stable and alpha coverage table.

Global coverage boundaries

Category non-claims

  • traditional endpoint antivirus
  • universal model-level prompt-injection filter
  • replacement for SCA or dependency scanning
  • support for every action in every harness

Channel limitations

  • stable: Coverage is harness- and event-specific.
  • stable: Scanning and runtime interception are separate controls.
  • stable: Guard does not claim universal model-level prompt filtering.
  • alpha: Alpha capabilities must be labeled alpha on public pages.
  • alpha: Coverage is harness- and event-specific.
  • alpha: Guard does not claim universal model-level prompt filtering.

Fail-open, crash, timeout, and blind-spot facts

These facts are derived from the same commit-pinned support contract used by the coverage table.

ChannelHarnessFail behaviorKnown boundaryEvidence
stableCodexsurface specificInline file edits applied directly by the model without a tool call are not visible to Guard.source commit
stableClaude Codesurface specificBackground agent sessions that run without an active terminal do not surface hook events to Guard.source commit
stableOpenCodesurface specificPrompt content is not currently surfaced through hooks.source commit
stableOpenCodesurface specificFile read/write events bypass Guard unless OpenCode permission rules block them.source commit
stableGitHub Copilot CLIsurface specificMCP tool calls routed through the VS Code extension are not visible to the CLI-level Guard hook.source commit
stableCursorsurface specificShell commands issued through Cursor's built-in terminal bypass Guard unless the terminal runs inside an agent session.source commit
stableCursorsurface specificPrompt submission is not surfaced through native Cursor hooks.source commit
stableClinesurface specificNative Cline PostToolUse hooks are observation-only; full output mediation requires the Guard-managed Cline plugin transport.source commit
stableClinesurface specificJetBrains protection is reported as unverified until a live pre-tool deny proof is observed.source commit
stableGemini CLIsurface specificPrompt submission events and file read/write operations are not currently observable through the Gemini hook surface.source commit
stableHermessurface specificHermes desktop and ACP entry paths may not register shell hooks; CLI and gateway honor hooks.pre_tool_call.source commit
stableOpenClawsurface specificShell commands and prompt events are not currently observable.source commit
stableOpenClawsurface specificGuard only intercepts MCP tool calls via the proxy layer.source commit
stableAntigravitysurface specificShell commands are not currently observable through the Antigravity hook surface; Guard intercepts extensions and MCP registrations via scan at launch time.source commit
stableKimi Codefail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
stableKimi Codefail openTool output post-processing and inline edits applied without a tool call are not visible to Guard.source commit
stableKimi Codefail openHooks run in parallel, so separate requests may be reviewed concurrently.source commit
stableGrok Buildfail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
stableGrok Buildfail openGrok UserPromptSubmit hooks are observe-only, so prompt screening cannot block the model from seeing the prompt.source commit
stableGrok Buildfail openEnforcement is the catch-all PreToolUse hook, including subagent and MCP tools.source commit
stableGrok Buildfail open--always-approve and bypassPermissions weaken Grok's own prompt policy, but the Guard hook still returns a native deny when policy blocks a tool call.source commit
stablePisurface specificPackage install and update flows happen outside the runtime extension bridge; Guard observes the configured package surfaces plus the prompt and tool events forwarded by the managed extension.source commit
stableOh My Pisurface specificPackage install and update flows happen outside the runtime extension bridge; Guard observes the configured package surfaces plus the prompt and tool events forwarded by the managed extension.source commit
stableZCodefail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
stableZCodefail openInline edits applied directly by the model without a tool call are not visible to Guard.source commit
stableZCodefail openBackground sessions that run without an active terminal do not surface hook events.source commit
alphaCodexsurface specificInline file edits applied directly by the model without a tool call are not visible to Guard.source commit
alphaClaude Codesurface specificBackground agent sessions that run without an active terminal do not surface hook events to Guard.source commit
alphaOpenCodesurface specificPrompt content is not currently surfaced through hooks.source commit
alphaOpenCodesurface specificFile read/write events bypass Guard unless OpenCode permission rules block them.source commit
alphaGitHub Copilot CLIsurface specificMCP tool calls routed through the VS Code extension are not visible to the CLI-level Guard hook.source commit
alphaCursorsurface specificShell commands issued through Cursor's built-in terminal bypass Guard unless the terminal runs inside an agent session.source commit
alphaCursorsurface specificPrompt submission is not surfaced through native Cursor hooks.source commit
alphaClinesurface specificNative Cline PostToolUse hooks are observation-only; full output mediation requires the Guard-managed Cline plugin transport.source commit
alphaClinesurface specificJetBrains protection is reported as unverified until a live pre-tool deny proof is observed.source commit
alphaGemini CLIsurface specificPrompt submission events and file read/write operations are not currently observable through the Gemini hook surface.source commit
alphaHermessurface specificHermes is an early-access harness; some event surface coverage depends on the Hermes version installed.source commit
alphaOpenClawsurface specificShell commands and prompt events are not currently observable.source commit
alphaOpenClawsurface specificGuard only intercepts MCP tool calls via the proxy layer.source commit
alphaAntigravitysurface specificShell commands are not currently observable through the Antigravity hook surface; Guard intercepts extensions and MCP registrations via scan at launch time.source commit
alphaKimi Codefail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
alphaKimi Codefail openTool output post-processing and inline edits applied without a tool call are not visible to Guard.source commit
alphaKimi Codefail openHooks run in parallel, so separate requests may be reviewed concurrently.source commit
alphaGrok Buildfail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
alphaGrok Buildfail openGrok UserPromptSubmit hooks are observe-only, so prompt screening cannot block the model from seeing the prompt.source commit
alphaGrok Buildfail openEnforcement is the catch-all PreToolUse hook, including subagent and MCP tools.source commit
alphaGrok Buildfail open--always-approve and bypassPermissions weaken Grok's own prompt policy, but the Guard hook still returns a native deny when policy blocks a tool call.source commit
alphaPisurface specificPackage install and update flows happen outside the runtime extension bridge; Guard observes the configured package surfaces plus the prompt and tool events forwarded by the managed extension.source commit
alphaOh My Pisurface specificPackage install and update flows happen outside the runtime extension bridge; Guard observes the configured package surfaces plus the prompt and tool events forwarded by the managed extension.source commit
alphaZCodefail openThe pinned support contract marks this adapter fail-open; a hook failure must not be described as fail-closed protection.source commit
alphaZCodefail openInline edits applied directly by the model without a tool call are not visible to Guard.source commit
alphaZCodefail openBackground sessions that run without an active terminal do not surface hook events.source commit

How to interpret a gap

A partial or unsupported surface means the public evidence does not justify describing that action as protected. It does not mean the harness is unsafe, and it does not mean another control cannot cover the gap. Coverage changes must update the commit-pinned support manifest before this page or comparison content can claim the new behavior.