Update an existing list with new properties. Use this tool to modify list details or settings.
AI agents use update_list to create or update resources in Trello — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Trello environment.
The tool modifies list configuration in Trello (a reversible operation). It does not delete data (which would be Destructive), execute external commands (Execute), or move money (Financial). The severity is medium rather than low because misconfigured list updates could affect team workflows, though changes are reversible. Confidence is high given the explicit language about updating and modifying.
From the tool's definition Tool description states 'Update an existing list with new properties' and 'modify list details or settings' — clear write operations that change existing data reversibly without deletion.
Documented attack patterns abuse exactly the kind of access update_list gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Trello, and nothing reaches the server without passing your rules. This is the rule we recommend for update_list:
{
"version": "1",
"default": "deny",
"tools": {
"update_list": {
"limits": [
{
"counter": "update_list_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}update_list 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.
Free to start. No card required.
Update an existing list with new properties. Use this tool to modify list details or settings. It is categorised as a Write tool in the Trello MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Trello MCP server in PolicyLayer and add a rule for update_list: 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 Trello. Nothing to install.
update_list is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the update_list 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 update_list. 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.
update_list is provided by the Trello MCP server (v4lheru/trello-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Trello, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
76 Trello tools catalogued and risk-classified — across an index of 43,000+ MCP servers.