Update an existing cycle. Provide id plus at least one other field to change.
AI agents use linear_updateCycle to create or update resources in Linear — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Linear environment.
This tool creates or modifies data reversibly by updating cycle attributes. It falls squarely within the Write category—it changes state in the Linear project management system but does not delete, execute external operations, or move money. The blast radius is medium because a malicious agent could modify planning cycles affecting team workflows, but changes are typically reversible through subsequent updates.
From the tool's definition Tool name contains 'update' and description states 'Update an existing cycle'. The operation modifies an existing resource (cycle) in a reversible manner.
Documented attack patterns abuse exactly the kind of access linear_updateCycle gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Linear, and nothing reaches the server without passing your rules. This is the rule we recommend for linear_updateCycle:
{
"version": "1",
"default": "deny",
"tools": {
"linear_updateCycle": {
"limits": [
{
"counter": "linear_updatecycle_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}linear_updateCycle 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 cycle. Provide id plus at least one other field to change. It is categorised as a Write tool in the Linear MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Linear MCP server in PolicyLayer and add a rule for linear_updateCycle: 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 Linear. Nothing to install.
linear_updateCycle 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 linear_updateCycle 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 linear_updateCycle. 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.
linear_updateCycle is provided by the Linear MCP server (tacticlaunch/mcp-linear). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 182 Linear tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
182 Linear tools catalogued and risk-classified — across an index of 42,500+ MCP servers.