Functions that agents
can actually find
MCP is the standard that makes your functions accessible to Claude, Cursor, Continue, Windsurf, Cline, and every other agent platform. Configure the FunctionFly MCP server once per agent — FunctionFly makes publishing MCP-compatible functions effortless.
Zero glue code
Your function runs on FunctionFly. Flip a toggle. It appears in the MCP Function Registry within ~30 seconds and becomes callable from any MCP-compatible agent.
Trust built in
Every MCP function carries its FunctionFly trust score, verification tier, and capability declarations. Agents can make informed decisions before they call.
Universal standard
MCP is adopted by Claude, Cursor, Continue, Windsurf, Cline, and dozens more. Configure once per agent — FunctionFly works with every MCP-compatible platform.
How it works
Publish your function
Deploy your function via the dashboard or API. FunctionFly bundles, signs, and verifies it.
Enable MCP
Flip the "MCP-compatible" toggle in the dashboard. Your function is listed in the MCP registry and callable via the FunctionFly MCP server.
Agents call tools/list
MCP clients call tools/list to fetch every enabled function. Agents that support .well-known auto-discovery connect without manual setup.
Call with confidence
Agents call over streamable-HTTP or stdio. FunctionFly enforces rate limits, logs every invocation, and updates trust scores.
Works with every agent
Claude Desktop
Add the FunctionFly MCP server to your Claude Desktop config and start calling functions.
Setup guide →Cursor
Enable the MCP server in Cursor's settings to unlock FunctionFly functions in your workflow.
Setup guide →Continue
Add FunctionFly as an MCP server in Continue's config to surface functions in your IDE.
Setup guide →Windsurf
Configure FunctionFly as an MCP server in Windsurf to access functions directly from the editor.
Setup guide →Cline
Add FunctionFly MCP server to Cline's configuration for AI-powered function calls.
Setup guide →Kilo Code
Configure FunctionFly as an MCP server in Kilo Code's configuration for AI-powered function calls.
Setup guide →Verified MCP badge
Functions can earn a Verified MCP badge by meeting standards that agents can trust at a glance.
Trust score 80+
Functions must have a trust score of 80 or higher, based on execution history and verification level.
Verified
Content-hash verified, malware scan passed, and approval given — no malicious code reaches agent toolchains.
100+ invocations
Real usage history proves the function works correctly in production at scale.
30+ days old
Stability over time gives agents confidence the function is maintained and reliable.
Technical details
Transport protocols
- → streamable-HTTP — Default, per MCP spec 2025-03-26
- → stdio — Via @functionflycom/mcp-server npm package
Rate limiting
- → 1–10,000 calls/min per function
- → Default: 60 calls/min
- → Configurable per-function in dashboard
Security
- → Bearer auth (JWT session or API key)
- → CORS allowlist per function
- → Input schema validation
- → 256 KiB max payload
JSON-RPC 2.0 methods
- → initialize, ping
- → tools/list, tools/all
- → resources/list, prompts/list
Ready to publish?
Join the registry and make your functions accessible to any MCP agent.