read_file

Read an uploaded file's contents by name.

SERVERAgent Jail SOURCEidiscoord13-sketch/agent-jail-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/agent-jail-mcp/read-file.md

WHAT IT DOES

What read_file does on Agent Jail

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

RISK

Why read_file is rated Low

This tool retrieves file contents from an uploaded file without modifying, deleting, or executing anything. It is a straightforward read operation with minimal risk. Severity is low because file access is constrained to already-uploaded files, limiting blast radius.

From the tool's definition Tool name 'read_file' and description 'Read an uploaded file's contents by name' both explicitly indicate retrieval of data with no modification or side effects.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs read_file safely

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

read_file Allowed

read_file 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": {
    "read_file": {}
  }
}

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

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

FAQ

Questions about read_file

What does the read_file tool do? +

Read an uploaded file's contents by name. It is categorised as a Read tool in the Agent Jail MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on read_file? +

Register the Agent Jail MCP server in PolicyLayer and add a rule for read_file: 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 Agent Jail. Nothing to install.

What risk level is read_file? +

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

Can I rate-limit read_file? +

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

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

read_file is provided by the Agent Jail MCP server (idiscoord13-sketch/agent-jail-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Agent Jail, and thousands of servers like it.

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claude_read_file on Claude Bridge → The MCP Attack Database →

Guides

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