customfields.updateCustomField · Gojira MCP: Risk & Policy

WHAT IT DOES

What customfields.updateCustomField does on Gojira

AI agents use customfields.updateCustomField to create or update resources in Gojira — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Gojira environment.

WHY IT NEEDS A POLICY

Why customfields.updateCustomField needs a policy

Updating a custom field in Jira is a reversible write operation that modifies configuration but does not delete data or execute arbitrary code. The blast radius is medium because misconfigured custom fields could disrupt project workflows, reporting, and issue tracking across teams, but the operation itself is not irreversible (updates can be reverted) and does not have financial implications.

From the tool's definition Tool name is "updateCustomField" and description states "Update a custom field". The verb "update" indicates modification of existing data.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

customfields.updateCustomField Rate-limited

customfields.updateCustomField stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "customfields.updateCustomField": {
      "limits": [
        {
          "counter": "customfields.updatecustomfield_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Gojira, so you can run agents against it safely.

FAQ

Questions about customfields.updateCustomField

What does the customfields.updateCustomField tool do? +

Update a custom field. It is categorised as a Write tool in the Gojira MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on customfields.updateCustomField? +

Register the Gojira MCP server in PolicyLayer and add a rule for customfields.updateCustomField: 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 Gojira. Nothing to install.

What risk level is customfields.updateCustomField? +

customfields.updateCustomField is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit customfields.updateCustomField? +

Yes. Add a rate_limit block to the customfields.updateCustomField 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 customfields.updateCustomField completely? +

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

customfields.updateCustomField is provided by the Gojira MCP server (windoze95/gojira-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.