MCP Gate (Preview)
Understand the ActionBox MCP policy adapter preview and the hosted MCP integration available to customers.
CLI bridge availability
The hosted MCP endpoint is available, but the CLI bridge's current standalone
release files are not available from the public download host. Treat the
actionbox mcp setup below as a reference for an already provisioned CLI
build until the CLI availability notice is removed.
ActionBox has a supported, hosted MCP server at
https://api.actionbox.cloud/mcp. The public CLI exposes it through a local
stdio bridge, so an MCP client can use ActionBox's human-input tools without
receiving a Source key in its JSON-RPC messages:
{
"mcpServers": {
"actionbox": {
"command": "actionbox",
"args": ["mcp"]
}
}
}Run actionbox configure first. It stores the Source credential in the CLI's
protected local configuration, and actionbox mcp forwards MCP messages to the
hosted ActionBox endpoint. See the Developer CLI guide for
installation and credential setup.
Deterministic policy adapter preview
The deterministic MCP Gate is a separate early preview of a policy adapter for
teams that need an explicit boundary before a local MCP tool runs. It is not a
generally available ActionBox command or a hosted ActionBox endpoint. The
supported public CLI command is actionbox mcp; there is no public
actionbox gate command.
ActionBox remains a hosted service. Do not copy preview-only installation commands or local server configuration into a customer integration. If your account has access to the Gate preview, use the account-specific preview instructions and keep it isolated from production automation until the preview is explicitly enabled for your account.
Policy behavior
The preview applies one explicit policy to each downstream tool call:
| Policy | Behavior | Verified boundary |
|---|---|---|
ALLOW | Executes the reviewed tool call immediately and records a content-free local audit event. | No Action is created. |
ASK | Creates an expiring Action containing the tool identity, call digests, and recursively redacted arguments; waits for a human decision and verifies the signed receipt before execution. | The approved call is bound to its action_version and fingerprint. |
DENY | Returns ACTIONBOX_GATE_DENIED without invoking the downstream tool or asking a human. | The default policy is DENY. |
The preview fails closed when the downstream tool is unknown, its identity or tool schema differs from the reviewed pin, the receipt cannot be verified, or the redacted argument display exceeds 20 KB. It wraps one downstream stdio MCP server and exact tool names; it does not provide wildcards, conditional rules, delegation, resources, prompts, or sampling.
Preview status
A local policy adapter is not a substitute for the hosted ActionBox API. Do not treat a waiting client timeout, a denied tool call, or a missing outcome report as a successful execution. The preview records a separate Action outcome only after the downstream call returns.
For the generally available integration, use the hosted MCP server through
actionbox mcp and let the ActionBox tools create and read durable Actions.
For the policy preview, contact ActionBox support for availability and the
current account-specific instructions.