Add an entry to a Redis stream with an optional expiration time. Args: key (str): The stream key. fields (dict): The fields and values for the stream entry. expiration (int, optional): Expiration time in seconds. Returns: str: The ID of the added entry or an error message.
AI agents use xadd to create or update resources in Redis MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Redis MCP Server environment.
This tool creates new entries in a Redis stream, which is a reversible write operation (entries can be deleted via 'delete' tool visible in sibling list). It does not execute arbitrary code, delete data irreversibly, move funds, or expose financial operations.
From the tool's definition Tool name 'xadd' and description 'Add an entry to a Redis stream' indicate data creation/modification. Args include 'key', 'fields' (data to store), and optional 'expiration', with return of 'The ID of the added entry' confirming successful write operation.
Documented attack patterns abuse exactly the kind of access xadd gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Redis MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for xadd:
{
"version": "1",
"default": "deny",
"tools": {
"xadd": {
"limits": [
{
"counter": "xadd_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}xadd stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Add an entry to a Redis stream with an optional expiration time. Args: key (str): The stream key. fields (dict): The fields and values for the stream entry. expiration (int, optional): Expiration time in seconds. Returns: str: The ID of the added entry or an error message. It is categorised as a Write tool in the Redis MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Redis MCP Server MCP server in PolicyLayer and add a rule for xadd: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Redis MCP Server. Nothing to install.
xadd is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the xadd rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for xadd. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
xadd is provided by the Redis MCP Server MCP server (redis/mcp-redis). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 53 Redis MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
53 Redis MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.