Use Foldr with Aider (MCP)
Aider is the popular open-source pair-programming CLI that edits your git repo from the terminal. Recent versions added experimental MCP support so Aider can call external tools during its edit loop. With Foldr wired up, Aider can upload generated diffs, build logs, or screenshots and paste the URL into a PR body.
Installation
Add the Foldr MCP server to Aider 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.
aider --mcp-server "npx -y @foldr/mcp-server" \
--mcp-env FOLDR_API_KEY=fs_live_...Setup tip: Or add the server block to ~/.aider.conf.yml under "mcp_servers:".
Official Aider MCP docsWhat You Can Do
- Upload any file from Aider 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
Aider + Foldr FAQ
How do I install the Foldr MCP server in Aider?
Open Aider'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 Aider if it doesn't hot-reload.
How much does it cost to use Foldr from Aider?
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 Aider says the Foldr tool isn't available - what's wrong?
Three common causes: (1) Aider 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 Aider's docs for the version that added MCP support.
Can Aider upload files directly to Foldr, or just generate URLs?
Aider 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 Aider can read from disk can be uploaded.
Is the Foldr MCP integration with Aider production-ready?
Foldr's MCP server is stable and used in production - streamable-http transport at https://foldr.space/api/mcp with 23 tools. Aider's MCP support is currently experimental - expect rough edges and breaking changes. Every write endpoint accepts an Idempotency-Key so retries are safe.
Related MCP Integrations
Connect Aider to Foldr in under a minute
Grab an API key, paste the snippet above into Aider's MCP config, top up credits (or grab a Pro subscription), and your agent can upload files and mint share links immediately.