catalyst-functions

name	catalyst-functions
description	Catalyst serverless functions — all 7 types (Basic I/O, Advanced I/O, Event, Cron, Job, Integration, Browser Logic), handler signatures, catalyst-config.json, Security Rules, API Gateway routing, file uploads, busboy, Express middleware, environment variables, function URL, and function testing. Trigger on 'write a function', 'catalyst function', 'API Gateway', 'Security Rules', 'function not found', 'function returns 401', 'busboy', 'middleware', 'function URL', 'environment variable in function', or any function type question. Do NOT use for persistent servers, long-running processes, WebSockets, or Docker deployments — use catalyst-appsail instead.
compatibility	Requires Catalyst CLI (`npm install -g zcatalyst-cli`) and Node.js v24 (recommended; v14–v22 lts also supported). Java functions also require JDK 8, 11, 17, 21 or 25. Python functions require Python 3.9, 3.10, 3.11, 3.12 or 3.13.
metadata	{"version":"2.0.0"}

How It Works

1. Establish MCP connection first — HARD STOP if not connected. Check whether CatalystbyZoho_* tools are available in the current tool list.

   • If available: Run CatalystbyZoho_List_All_Organizations → CatalystbyZoho_List_All_Projects to set project context, then proceed to step 2.
   • If NOT available: Do NOT write any code, scaffold any files, or run any CLI commands. Present the two options below and wait for the user to confirm CatalystbyZoho_* tools are visible before continuing.

   ---

   To use Catalyst via AI, you need the Zoho MCP Global Server connected. Add a single URL to your AI client config, authorize once via browser, and you're done.

   Claude Desktop — edit ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

   { "mcpServers": { "catalyst-by-zoho": { "type": "streamable-http", "url": "https://catalyst.zohomcp.com/mcp/message" } } }
   

   Restart your AI client → authorize via browser when prompted → look for CatalystbyZoho_* tools to confirm.

   ---

2. Check local scaffold — never run interactive CLI commands. Verify .catalystrc and catalyst.json exist. If missing, do NOT run catalyst init yourself — the CLI uses interactive arrow-key menus that cannot be reliably controlled from a terminal session. Instead, ask the user to run it:

   Please run catalyst init in your terminal, select your project and choose "Configure and deploy http/non-http functions" when asked which features to set up. Come back once done. Wait for confirmation before continuing.

3. Identify the function type — Basic I/O for simple request/response, Advanced I/O for raw HTTP control, Event for trigger-based, Cron/Job for scheduled, Integration for Zoho service events, Browser Logic for Puppeteer.

4. Load references/functions-basics.md — for the matching handler signature, catalyst-config.json keys, SDK init pattern, and CORS setup.

5. Load references/functions-advanced.md — for file uploads (busboy), streaming responses, error handling, or chaining functions.

6. Load references/api-gateway.md — for routing rules, rate limiting, or gateway-level CORS.

7. Validate config — Confirm catalyst-config.json uses deployment + execution keys only. Never use function or entry_point.

Security Checklist

• Functions are publicly accessible by default. Security Rules sets authentication to optional when a function is created — its URL is globally accessible to everyone with no restrictions. Set "authentication": "required" in the Security Rules JSON for any function that reads or writes user data or sensitive resources.
• API Gateway replaces Security Rules — do not use both. Enabling API Gateway automatically disables Security Rules. Pick one auth/routing layer per function.

Triggers

Use this skill for: "write a function", "catalyst function", "Basic I/O", "Advanced I/O", "Event function", "Cron function", "Browser Logic", catalyst-config.json, "function handler", "API Gateway", "rate limiting", "busboy", "file upload in function", catalyst deploy --only functions:<function-name>, catalyst functions:add, "function CORS", or any function type or function configuration question.

Deployment command note:

• Use catalyst deploy --only functions:<function-name> to deploy one function (where functions:<name> targets the function by its folder name).
• Use catalyst deploy --only functions to deploy all functions at once.

References

Reference	Load when the query is about…
references/functions-basics.md	Start here for any function question. Function type selection, Basic I/O and Advanced I/O handler signatures, catalyst-config.json, user-scope vs admin-scope, CORS, Security Rules, execution limits
references/functions-advanced.md	Advanced I/O patterns only. Express vs raw-http template differences, file uploads (busboy), streaming files from Stratus, error handling patterns, CORS for local dev, local testing, function chaining, ZCQL result unwrapping, HTTP payload limits
references/functions-templates.md	Event, Cron, Job, or Integration functions. Handler templates for all background/scheduled types, SDK component reference, retry behavior, cold start data, and the full common errors table
references/api-gateway.md	API Gateway config only. Enable/disable gateway, routing rules, rate limiting, CORS via gateway