Compatible with every major AI agent and IDE
What is the JSONPlaceholder MCP Server?
Connect to JSONPlaceholder, the industry-standard fake REST API, to simulate data interactions within your AI workflows. Perfect for developers testing MCP integrations or prototyping agentic behaviors without a real backend.
What you can do
- Post Management — Use
list_posts,get_post,create_post,update_post,patch_post, anddelete_postto test full CRUD lifecycles. - Social Interactions — Query comments via
list_commentsandget_commentto simulate discussion threads and linking. - Media Handling — Explore
list_albums,get_album,list_photos, andget_phototo manage hierarchical media metadata. - Task Tracking — Use
list_todosto verify state-based logic and completion status in your agents. - Data Filtering — Test precise data retrieval by filtering lists by
userId,postId, oralbumIddirectly through tool parameters.
How it works
- Subscribe to this server
- No real API key is required for this public service, but you can provide a placeholder string if prompted
- Start prototyping your data-driven agents immediately
Who is this for?
- MCP Developers — verify that your client correctly handles tool calls, pagination, and JSON responses
- AI Researchers — prototype complex agent behaviors that require structured data interaction without setting up a database
- Product Designers — demonstrate AI-driven workflows using realistic (but safe) mock data
Built-in capabilities (21)
Create a new post
Delete a post
Get a specific album by ID
Get photos for a specific album
Get a specific comment by ID
Get a specific photo by ID
Get a specific post by ID
Get comments for a specific post
Get a specific todo by ID
Get a specific user by ID
Get albums for a specific user
Get posts for a specific user
Get todos for a specific user
Can be filtered by userId. List all albums
Can be filtered by postId. List all comments
Can be filtered by albumId. List all photos
Can be filtered by userId. List all posts
Can be filtered by userId. List all todos
List all users
Update a post (partial)
Update a post (replace)
Why Cursor?
Cursor's Agent mode turns JSONPlaceholder into an in-editor superpower. Ask Cursor to generate code using live data from JSONPlaceholder and it fetches, processes, and writes. all in a single agentic loop. 21 tools appear alongside file editing and terminal access, creating a unified development environment grounded in real-time information.
- —
Agent mode turns Cursor into an autonomous coding assistant that can read files, run commands, and call MCP tools without switching context
- —
Cursor's Composer feature can generate entire files using real-time data fetched through MCP. no copy-pasting from external dashboards
- —
MCP tools appear alongside built-in tools like file reading and terminal access, creating a unified agentic environment
- —
VS Code extension compatibility means your existing workflow, keybindings, and extensions all work alongside MCP tools
JSONPlaceholder in Cursor
JSONPlaceholder and 4,000+ other MCP servers. One platform. One governance layer.
Teams that connect JSONPlaceholder to Cursor through Vinkius don't need to source, host, or maintain individual MCP servers. Every tool call runs inside a hardened runtime with credential isolation, DLP, and a signed audit chain.
Raw MCP | Vinkius | |
|---|---|---|
| Server catalog | Find and host yourself | 4,000+ managed |
| Infrastructure | Self-hosted | Sandboxed V8 isolates |
| Credential handling | Plaintext in config | Vault + runtime injection |
| Data loss prevention | None | Configurable DLP policies |
| Kill switch | None | Global instant shutdown |
| Financial circuit breakers | None | Per-server limits + alerts |
| Audit trail | None | Ed25519 signed logs |
| SIEM log streaming | None | Splunk, Datadog, Webhook |
| Honeytokens | None | Canary alerts on leak |
| Custom domains | Not applicable | DNS challenge verified |
| GDPR compliance | Manual effort | Automated purge + export |
Why teams choose Vinkius for JSONPlaceholder in Cursor
The JSONPlaceholder MCP Server runs on Vinkius-managed infrastructure inside AWS — a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts. All 21 tools execute in hardened sandboxes optimized for native MCP execution.
Your AI agents in Cursor only access the data you authorize, with DLP that blocks sensitive information from ever reaching the model, kill switch for instant shutdown, and up to 60% token savings. Enterprise-grade infrastructure, zero maintenance.

* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure
How Vinkius secures
JSONPlaceholder for Cursor
Every tool call from Cursor to the JSONPlaceholder MCP Server is protected by DLP redaction, cryptographic audit chains, V8 sandbox isolation, kill switch, and financial circuit breakers.
Frequently asked questions
Can I filter posts by a specific user?
Yes! Use the list_posts tool with the userId parameter to retrieve only the posts created by that specific user ID.
Does creating or updating a post actually save the data?
No. JSONPlaceholder is a fake API. Tools like create_post, update_post, and delete_post simulate the response as if the action succeeded, but the server state remains unchanged.
How do I find comments for a specific post?
Use the list_comments tool and provide the postId. This will return all comments associated with that specific post ID.
What is Agent mode and why does it matter for MCP?
Agent mode is Cursor's autonomous execution mode where the AI can perform multi-step tasks: reading files, editing code, running terminal commands, and calling MCP tools. Without Agent mode, Cursor operates in a simpler ask-and-answer mode that doesn't support tool calling. Always ensure you're in Agent mode when working with MCP servers.
Where does Cursor store MCP configuration?
Cursor looks for MCP server configurations in a mcp.json file. You can configure servers at the project level (.cursor/mcp.json in your project root) or globally (~/.cursor/mcp.json). Project-level configs take precedence.
Can Cursor use MCP tools in inline edits?
No. MCP tools are only available in Agent mode through the chat panel. Inline completions and Tab suggestions do not trigger MCP tool calls. This is by design. tool calls require user visibility and approval.
How do I verify MCP tools are loaded?
Open Settings → Features → MCP and look for your server name. A green indicator means the server is connected. You can also check Agent mode's available tools by clicking the tools dropdown in the chat panel.
Tools not appearing in Cursor
Ensure you are in Agent mode (not Ask mode). MCP tools only work in Agent mode.
Server shows as disconnected
Check Settings → Features → MCP and verify the server status. Try clicking the refresh button.
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