list_variables
List account variable NAMES (values are write-only — they are injected into proxy calls and container apps, never read back).
This record as markdown: /tools/ai-dataecho-mcp/list-variables.md
What list_variables does on Mcp
AI agents call list_variables to retrieve information from Mcp without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Why list_variables is rated Low
This tool retrieves metadata about variables (their names) without accessing sensitive values. It has no side effects, does not modify or delete data, and does not execute code or trigger external operations. The explicit design that values are write-only and never read back confirms this is a safe information-retrieval action with minimal blast radius if misused by an AI agent.
From the tool's definition Tool description states 'List account variable NAMES' and explicitly notes 'values are write-only — they are injected into proxy calls and container apps, never read back.' The verb 'list' and the retrieval-only nature (names only, no sensitive values)…
Attacks that exploit this kind of access
The rule that runs list_variables safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Mcp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For list_variables, this is the rule to start with:
list_variables is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Mcp, apply this rule, and every list_variables call is checked against it from then on.
Questions about list_variables
List account variable NAMES (values are write-only — they are injected into proxy calls and container apps, never read back). It is categorised as a Read tool in the Mcp MCP Server, which means it retrieves data without modifying state.
Register the MCP server in PolicyLayer and add a rule for list_variables: 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 Mcp. Nothing to install.
list_variables is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the list_variables 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 list_variables. 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.
list_variables is provided by the MCP server (https://dataecho.ai/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on , and thousands of servers like it.
This server
Across the catalogue