Cursor: Plugins, Sandbox Access Controls, and Async Subagents

The Cursor Marketplace: Plugins for the Full Development Lifecycle

Cursor 2.5 introduces the Cursor Marketplace, a new distribution channel for plugins that combine MCP servers, skills, subagents, rules, and hooks into a single installable unit. Rather than configuring each of these components separately, developers can now install a single plugin to gain structured, context-aware access to an external tool or platform.

The marketplace launches with an initial set of partners spanning the key layers of a typical development workflow: Amplitude for analytics, AWS for infrastructure, Figma for design, Linear for project management, and Stripe for payments. Plugins are browsable at cursor.com/marketplace and installable directly from within Cursor using the /add-plugin command.

The plugin system represents a significant shift in how Cursor extends its capabilities. Previously, integrations required manual MCP server configuration and separately authored skill files. Plugins collapse that setup into a single action, and because each plugin can include its own bundled subagents and rules, the resulting experience is more coherent and context-aware than ad-hoc MCP configurations.

Async Subagents: Parallel Execution Without Blocking

Prior to 2.5, subagents ran synchronously — each one had to complete before the parent agent could proceed. Cursor 2.5 changes this fundamentally. Subagents now execute asynchronously in the background, freeing the parent agent to continue working on other tasks in parallel.

This architectural change unlocks a new class of workloads. A parent agent can now dispatch multiple subagents concurrently to tackle independent parts of a large feature — one handling database migrations, another updating API contracts, a third writing tests — and collect their results as they complete. Subagents themselves can spawn child subagents, enabling coordinated multi-level work trees for sufficiently complex tasks.

The practical performance improvements are measurable: Cursor reports lower latency, better streaming feedback as work progresses, and genuinely responsive parallel execution rather than sequential queuing.

Sandbox Network Access Controls

Cursor 2.5 introduces granular network access controls for the sandbox environment, giving individual developers and enterprise administrators significantly more control over what network destinations sandboxed agents can reach.

Three configuration modes are available: "User config only" restricts access strictly to domains listed in sandbox.json; "User config with defaults" combines the user's allowlist with Cursor's built-in default destinations; and "Allow all" removes network restrictions entirely. Enterprise administrators can go further, enforcing organization-wide allowlists and denylists through the admin dashboard.

Quality-of-Life Improvements

Cursor 2.5 ships sixteen additional improvements alongside the headline features:

• Chat history is now searchable and can be referenced as context within conversations
• The CLI agent handles sudo password prompts inline
• Common package manager and version control operations work out of the box within the sandbox
• Plan mode now offers a Cloud Agent handoff option
• Inline diffs can be toggled on or off
• "Duplicate Chat" has been renamed to "Fork Chat"
• Long chat performance has been optimized

Bug Fixes

Seven bugs were resolved, including terminal tool call performance degradation, keybinding issues, unintended auto-run mode switching, and proper termination of child subagents when stopping a parent agent.