client_dms

A read tool on the Slack MCP server.

SERVERSlack SOURCEkarbassi/slack-mcp

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/karbassi-slack-mcp/client-dms.md

WHAT IT DOES

What client_dms does on Slack

AI agents call client_dms to retrieve information from Slack without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why client_dms is rated Low

The tool name 'client_dms' most likely refers to listing or retrieving direct messages. The server context includes many read-oriented tools. However, the empty description lowers confidence significantly. DM access carries medium severity due to potentially sensitive private communications.

From the tool's definition Tool name 'client_dms' and empty description; 'dms' suggests direct messages, likely a read/list operation based on context of sibling tools (activity_feed, ai_summarize_unreads_snapshot, etc.)

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs client_dms safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Slack, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For client_dms, this is the rule to start with:

client_dms Allowed

client_dms is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "client_dms": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Slack, apply this rule, and every client_dms call is checked against it from then on.

FAQ

Questions about client_dms

What does the client_dms tool do? +

client_dms is a read tool on the Slack MCP server. It is categorised as a Read tool in the Slack MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on client_dms? +

Register the Slack MCP server in PolicyLayer and add a rule for client_dms: 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 Slack. Nothing to install.

What risk level is client_dms? +

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

Can I rate-limit client_dms? +

Yes. Add a rate_limit block to the client_dms 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 client_dms completely? +

Set action: deny in the PolicyLayer policy for client_dms. 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 client_dms? +

client_dms is provided by the Slack MCP server (karbassi/slack-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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