Use Foldr with Block Goose (MCP)
Goose is Block's (formerly Square) open-source agent, designed as a local-first MCP client with a polished desktop app. Goose was one of the first non-Anthropic apps to build a full MCP experience. Foldr is a natural companion - Goose handles planning and local execution, Foldr handles publishing.
Installation
Add the Foldr MCP server to Block Goose 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.
# CLI goose configure → "Add Extension" → "Command-line Extension" → Command: npx -y @foldr/mcp-server → Env: FOLDR_API_KEY=fs_live_... # Or edit ~/.config/goose/config.yaml directly
What You Can Do
- Upload any file from Block Goose 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
Block Goose + Foldr FAQ
How do I install the Foldr MCP server in Block Goose?
Open Block Goose'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 Block Goose if it doesn't hot-reload.
How much does it cost to use Foldr from Block Goose?
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 Block Goose says the Foldr tool isn't available - what's wrong?
Three common causes: (1) Block Goose 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 Block Goose's docs for the version that added MCP support.
Can Block Goose upload files directly to Foldr, or just generate URLs?
Block Goose 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 Block Goose can read from disk can be uploaded.
Is the Foldr MCP integration with Block Goose production-ready?
Foldr's MCP server is stable and used in production - streamable-http transport at https://foldr.space/api/mcp with 23 tools. Block Goose's MCP support is currently stable and generally available. Every write endpoint accepts an Idempotency-Key so retries are safe.
Related MCP Integrations
Connect Block Goose to Foldr in under a minute
Grab an API key, paste the snippet above into Block Goose's MCP config, top up credits (or grab a Pro subscription), and your agent can upload files and mint share links immediately.