Cancel one or more running tasks. Accepts a single task_id or an array. Running tasks are aborted and marked `cancelled`. Already-terminal tasks are listed under `already_terminal`; unknown IDs under `not_found`.
Single-target operation
Part of the Mcp Codex Worker MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.
AI agents may call cancel-task to permanently remove or destroy resources in Mcp Codex Worker. Without a policy, an autonomous agent could delete critical data in a loop with no way to undo the damage. Intercept blocks destructive tools by default and requires explicit human approval before enabling them.
Without a policy, an AI agent could call cancel-task in a loop, permanently destroying resources in Mcp Codex Worker. There is no undo for destructive operations. Intercept blocks this tool by default and only allows it when a human explicitly approves the action.
Destructive tools permanently remove data. Block by default. Only enable with explicit approval workflows.
tools:
cancel-task:
rules:
- action: deny
reason: "Blocked by default — enable with approval"See the full Mcp Codex Worker policy for all 5 tools.
Agents calling destructive-class tools like cancel-task have been implicated in these attack patterns. Read the full case and prevention policy for each:
Other tools in the Destructive risk category across the catalogue. The same policy patterns (deny, require_approval) apply to each.
cancel-task is one of the critical-risk operations in Mcp Codex Worker. For the full severity-focused view — only the critical-risk tools with their recommended policies — see the breakdown for this server, or browse all critical-risk tools across every MCP server.
Cancel one or more running tasks. Accepts a single task_id or an array. Running tasks are aborted and marked `cancelled`. Already-terminal tasks are listed under `already_terminal`; unknown IDs under `not_found`.. It is categorised as a Destructive tool in the Mcp Codex Worker MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Add a rule in your Intercept YAML policy under the tools section for cancel-task. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Mcp Codex Worker MCP server.
cancel-task is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the cancel-task rule in your Intercept 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 Intercept policy for cancel-task. 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.
cancel-task is provided by the Mcp Codex Worker MCP server (mcp-codex-worker). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Open source. One binary. Zero dependencies.
npx -y @policylayer/intercept