temporal.namespace.list

THE RISK

Low Risk

Why temporal.namespace.list needs a policy

This tool retrieves namespace information from a Temporal cluster without side effects. It queries existing data and returns results. The read-only nature of the server and the passive listing operation place this firmly in the Read category. Severity is low because listing namespaces exposes metadata but does not affect system state or enable further privileged operations on its own.

From the tool's definition Tool description states 'List all namespaces' with no modification or destructive capability. Server description emphasizes 'read-only access to Temporal infrastructure'. The verb 'list' is a quintessential read operation.

Documented attack patterns abuse exactly the kind of access temporal.namespace.list gives an agent:

POLICY

How to control temporal.namespace.list

PolicyLayer is an MCP gateway — it sits between your AI agents and Temporal, and nothing reaches the server without passing your rules. This is the rule we recommend for temporal.namespace.list:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "temporal.namespace.list": {}
  }
}

temporal.namespace.list is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

Create a free account and register Temporal — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Temporal tools

Execute temporal.workflow.query Query a running workflow execution using a named query handler. Write docs.refresh Refresh the local Temporal documentation corpus by syncing with the latest docs. Read docs.get Get the full content of a specific documentation page. Read docs.search Search the Temporal documentation corpus for relevant information. Read docs.status Check the status of the local Temporal documentation corpus. Read temporal.cluster.info Get system information about the Temporal cluster including server version and capabilitie Read temporal.connection.check Check connectivity to a Temporal cluster by fetching system info. Read temporal.namespace.describe Get detailed information about a specific namespace.

All 28 Temporal tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about temporal.namespace.list

What does the temporal.namespace.list tool do? +

List all namespaces in a self-hosted Temporal cluster. It is categorised as a Read tool in the Temporal MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on temporal.namespace.list? +

Register the Temporal MCP server in PolicyLayer and add a rule for temporal.namespace.list: 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 Temporal. Nothing to install.

What risk level is temporal.namespace.list? +

temporal.namespace.list is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit temporal.namespace.list? +

Yes. Add a rate_limit block to the temporal.namespace.list 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.

How do I block temporal.namespace.list completely? +

Set action: deny in the PolicyLayer policy for temporal.namespace.list. 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.

What MCP server provides temporal.namespace.list? +

temporal.namespace.list is provided by the Temporal MCP server (stevekinney/temporal-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Temporal tool call.

Start from Temporal, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →