CLI & Terminal

Use Foldr with OpenAI Codex CLI (MCP)

Codex CLI is OpenAI's lightweight terminal agent that runs the o-series and GPT-5-class models locally against your repo. Codex CLI supports MCP servers for external tools alongside its shell and file-edit primitives. Connecting Foldr lets Codex share generated artifacts without leaving the agent loop.

OpenAImacOS, Linux, WindowsMCP: beta

Installation

Add the Foldr MCP server to OpenAI Codex CLI with the snippet below. Replace fs_… with an API key from foldr.space/developers/signup. Each upload costs 5¢ - top up account credits or subscribe to Pro tier to bypass per-call charges.

codex mcp add foldr \
  --env FOLDR_API_KEY=fs_live_... \
  -- npx -y @foldr/mcp-server

Setup tip: Or edit ~/.codex/config.toml and add an [mcp_servers.foldr] block.

Official OpenAI Codex CLI MCP docs

What You Can Do

Upload any file from OpenAI Codex CLI to Foldr and get a permanent shareable URL back in the same turn (5¢ per upload, debited from credits)
Mint short-lived capability tokens to share files with downstream agents without leaking your API key
Organize uploads into per-API-key folders with hierarchical structure
Shorten long URLs to foldr.space/s/... links - free with any API key
Hand off build artifacts, screenshots, and logs to a URL without leaving your editor

OpenAI Codex CLI + Foldr FAQ

How do I install the Foldr MCP server in OpenAI Codex CLI?

Open OpenAI Codex CLI's MCP configuration (the CLI) and paste the config block shown above. Set FOLDR_API_KEY to a key you create at foldr.space/developers/signup. Restart OpenAI Codex CLI if it doesn't hot-reload.

How much does it cost to use Foldr from OpenAI Codex CLI?

Each upload costs 5¢. You can pay by topping up account credits via the `top_up_credits` MCP tool (min $5) - every upload then debits from balance. Or subscribe to Pro tier ($25/mo) and per-call charges are bypassed entirely. Tools that don't write data (list_files, mint_capability, get_usage, etc.) are free.

I set the key but OpenAI Codex CLI says the Foldr tool isn't available - what's wrong?

Three common causes: (1) OpenAI Codex CLI wasn't restarted after editing the config - most MCP hosts need a restart to pick up new servers. (2) The API key is wrong or missing - verify the env var name your client reads (e.g. FOLDR_API_KEY) matches the config snippet above. (3) Your client doesn't support the streamable-http transport - most modern clients do, but check OpenAI Codex CLI's docs for the version that added MCP support.

Can OpenAI Codex CLI upload files directly to Foldr, or just generate URLs?

OpenAI Codex CLI can do both. The MCP server exposes tools for `upload_file` (base64-encoded file content), `bulk_upload` (up to 20 files in one call), `mint_capability` (short-lived shareable links), and `create_short_url`. Any file OpenAI Codex CLI can read from disk can be uploaded.

Is the Foldr MCP integration with OpenAI Codex CLI production-ready?

Foldr's MCP server is stable and used in production - streamable-http transport at https://foldr.space/api/mcp with 23 tools. OpenAI Codex CLI's MCP support is currently in public beta - suitable for day-to-day use. Every write endpoint accepts an Idempotency-Key so retries are safe.

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Connect OpenAI Codex CLI to Foldr in under a minute

Grab an API key, paste the snippet above into OpenAI Codex CLI's MCP config, top up credits (or grab a Pro subscription), and your agent can upload files and mint share links immediately.

Get your Foldr API key x402 details