@functionflycom/mcp-server

MCP server for FunctionFly — enables AI agents (Claude Desktop, Cursor, etc.) to interact with the FunctionFly platform directly.

Features

• Registry search — Find functions by name, author, runtime, or keyword
• Function execution — Execute any public or private function with JSON input
• Function publishing — Publish new functions or versions with source code and manifest
• Agent marketplace — Search and execute AI agents
• Usage analytics — View call counts and compute usage for your tenant
• Cost analytics — View cost breakdown by function
• Vault secrets — Zero-knowledge secret storage with client-side AES-256-GCM encryption
• StateFabric — Stateful workflow execution — list fabrics, pipelines, and trigger pipeline runs

Installation

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "functionfly": {
      "command": "npx",
      "args": ["-y", "@functionflycom/mcp-server"],
      "env": {
        "FUNCTIONFLY_API_KEY": "ffp_your_api_key_here"
      }
    }
  }
}

Cursor

Add to your Cursor MCP settings (Settings → MCP → Add new server):

{
  "mcpServers": {
    "functionfly": {
      "command": "npx",
      "args": ["-y", "@functionflycom/mcp-server"],
      "env": {
        "FUNCTIONFLY_API_KEY": "ffp_your_api_key_here"
      }
    }
  }
}

Configuration

Environment Variable	Required	Default	Description
FUNCTIONFLY_API_KEY	Yes	—	Your FunctionFly API key (starts with ffp_)
FUNCTIONFLY_API_URL	No	https://api.functionfly.com	API base URL
FUNCTIONFLY_EXECUTION_TIMEOUT_MS	No	30000	Execution timeout (ms, max 300000)
LOG_LEVEL	No	info	Log level: debug, info, warn, error
VAULT_PASSPHRASE	For vault tools	—	Passphrase for AES-256-GCM vault encryption/decryption

Available Tools

Registry Tools

registry_search_functions

Search the public function registry.

{
  "query": "image processing",
  "runtime": "python",
  "page": 1,
  "limit": 20
}

registry_get_function

Get metadata for a specific function.

{
  "author": "acme",
  "name": "resize-image"
}

registry_execute_function

Execute a function and get its result.

{
  "author": "acme",
  "name": "resize-image",
  "input": { "url": "https://example.com/image.jpg", "width": 800 },
  "version": "1.2.3"
}

registry_publish_function

Publish a new function or version to the registry. Requires authentication.

{
  "author": "acme",
  "name": "resize-image",
  "version": "1.2.3",
  "manifest": {
    "runtime": "python3.12",
    "description": "Resize an image to specified dimensions",
    "timeout_ms": 10000,
    "memory_mb": 256,
    "public": true,
    "deterministic": false,
    "input_schema": {
      "type": "object",
      "properties": {
        "url": { "type": "string", "description": "Image URL" },
        "width": { "type": "integer", "description": "Target width" }
      },
      "required": ["url"]
    }
  },
  "source": {
    "code": "import requests\nfrom PIL import Image\n...\nreturn {'url': output_url}",
    "runtime": "python3.12"
  },
  "changelog": {
    "category": "feature",
    "title": "Add width-only resize support",
    "description": "Image can now be resized by width alone while preserving aspect ratio",
    "changes": [
      {
        "component": "input schema",
        "field": "height",
        "description": "Made height optional"
      }
    ]
  }
}

Agent Tools

agents_search

Search the agent marketplace.

{
  "query": "data analysis",
  "page": 1,
  "limit": 20
}

agents_execute

Execute an agent by ID.

{
  "agentId": "agent_abc123",
  "input": { "data": "some input data" }
}

Analytics Tools

analytics_get_usage

Get usage metrics for your tenant.

{
  "startDate": "2024-06-01",
  "endDate": "2024-06-30",
  "granularity": "day"
}

analytics_get_costs

Get cost breakdown for your tenant.

{
  "startDate": "2024-06-01",
  "endDate": "2024-06-30",
  "groupBy": "function"
}

Vault Tools (Zero-Knowledge)

Zero-knowledge architecture: Secrets are encrypted client-side before leaving your machine. The FunctionFly server stores only ciphertext. Set VAULT_PASSPHRASE to control encryption.

vault_list_secrets

List secrets in your vault (metadata only, no values).

{
  "namespace": "production",
  "limit": 20,
  "offset": 0
}

vault_get_secret

Get and decrypt a secret. Uses VAULT_PASSPHRASE env var for decryption.

{
  "id": "550e8400-e29b-41d4-a716-446655440000"
}

vault_set_secret

Create a new secret. The value is encrypted client-side before upload. Uses VAULT_PASSPHRASE env var.

{
  "name": "github-api-key",
  "value": "ghp_xxxx",
  "secret_type": "api_key",
  "description": "GitHub personal access token",
  "namespace": "production"
}

vault_delete_secret

Permanently delete a secret by ID.

{
  "id": "550e8400-e29b-41d4-a716-446655440000"
}

StateFabric Tools (Stateful Workflows)

statefabric_list_fabrics

List all stateful workflows (StateFabrics) for your tenant.

{
  "limit": 20,
  "offset": 0
}

statefabric_get_fabric

Get details of a specific StateFabric.

{
  "id": "f47ac10b-58cc-4372-a567-0e02b2c3d479"
}

statefabric_list_pipelines

List all pipelines within a StateFabric.

{
  "fabricId": "f47ac10b-58cc-4372-a567-0e02b2c3d479",
  "limit": 20,
  "offset": 0
}

statefabric_execute_pipeline

Execute a pipeline within a StateFabric and return its result.

{
  "fabricId": "f47ac10b-58cc-4372-a567-0e02b2c3d479",
  "pipelineId": "a1b2c3d4-5678-90ab-cdef-1234567890ab",
  "input": { "key": "value" }
}

Error Codes

MCP Code	Meaning
-32001	Invalid API key
-32002	Function not found or execution error
-32003	Rate limited (after retry exhaustion)
-32004	Network or timeout error
-32005	Payment required (insufficient balance)
-32006	Quota exceeded

Security

MVP limitation: The MCP server uses a single API key for all operations. Any AI agent with access to the MCP server can perform any action your API key allows (publish functions, execute paid functions, spend credits, etc.). Use a scoped API key with minimal permissions for MCP integrations. A future release will introduce MCP-scoped API keys with restricted permissions.

All API keys are redacted from logs. Sensitive fields (secret, token, ciphertext, etc.) are also redacted.

Development

# Install dependencies
npm install

# Type check
npm run typecheck

# Lint
npm run lint

# Test
npm test

# Build
npm run build

# Run locally
FUNCTIONFLY_API_KEY=ffp_test ./dist/index.js

Publishing

Create a git tag to trigger an npm release:

git tag v1.0.0
git push origin v1.0.0

The release workflow will build, publish to npm, and create a GitHub release automatically.

License

MIT