query_dead_letter_queue

Query jobs in the dead letter queue

SERVERBullMQ MCP Server SOURCEadamhancock/bullmq-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/adamhancock-bullmq-mcp/query-dead-letter-queue.md

WHAT IT DOES

What query_dead_letter_queue does on BullMQ MCP Server

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

RISK

Why query_dead_letter_queue is rated Low

This tool queries (retrieves and examines) jobs in a dead letter queue, which is a read-only operation with no side effects. It does not modify, delete, execute, or move jobs—it only inspects their state. The blast radius of misuse is minimal; an attacker could only gain visibility into failed jobs.

From the tool's definition Tool name 'query_dead_letter_queue' and description 'Query jobs in the dead letter queue' indicate a retrieval operation that reads/inspects existing data without modification or deletion.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs query_dead_letter_queue safely

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

query_dead_letter_queue Allowed

query_dead_letter_queue 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": {
    "query_dead_letter_queue": {}
  }
}

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

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

FAQ

Questions about query_dead_letter_queue

What does the query_dead_letter_queue tool do? +

Query jobs in the dead letter queue. It is categorised as a Read tool in the BullMQ MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on query_dead_letter_queue? +

Register the BullMQ MCP Server MCP server in PolicyLayer and add a rule for query_dead_letter_queue: 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 BullMQ MCP Server. Nothing to install.

What risk level is query_dead_letter_queue? +

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

Can I rate-limit query_dead_letter_queue? +

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

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

query_dead_letter_queue is provided by the BullMQ MCP Server MCP server (adamhancock/bullmq-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on BullMQ MCP Server, and thousands of servers like it.

This server

All 20 BullMQ MCP Server tools →

Across the catalogue

claude_query on Claude Bridge → The MCP Attack Database →

Guides

Roll out MCP under one policy →Data exfiltration →MCP token cost →