AI agents call list_custom_fields to retrieve information from Redmine without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves/queries custom field metadata from Redmine. It performs no modifications, deletions, or external operations. The admin privilege requirement is a gating mechanism that controls who can access the data, but does not change the nature of the operation itself. Misuse would leak configuration information about custom fields, which is a read-level risk with low blast radius.
From the tool's definition Tool name is 'list_custom_fields' and description states it 'List custom fields', which is a retrieval operation with no side effects.
Risk signalsAdmin/system-level operation
Attacks that exploit this kind of access
List custom fields. Requires admin privileges; returns 403 otherwise. It is categorised as a Read tool in the Redmine MCP Server, which means it retrieves data without modifying state.
Register the Redmine MCP server in PolicyLayer and add a rule for list_custom_fields: 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 Redmine. Nothing to install.
list_custom_fields 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_custom_fields 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_custom_fields. 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_custom_fields is provided by the Redmine MCP server (KalvadTech/redmine-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →