Create MCP Server

Create MCP Servers with MCPHero

MCPHero lets agents build their own tools. Instead of burning tokens on API schemas, SQL queries, and output parsing every run, the agent creates a persistent MCP server once and calls it forever. A 50,000-token integration becomes a 50-token tool call.

This skill covers the mcpheroctl CLI workflow for building servers end-to-end.

Production API base URL: https://api.mcphero.app/api

Prerequisites

Before using this skill, the user must have mcpheroctl installed and authenticated.

Install mcpheroctl

# via Homebrew (macOS/Linux)
brew install arterialist/mcpheroctl/mcpheroctl

# via uv (cross-platform)
uv tool install mcpheroctl

Authenticate

1. Log in to the MCPHero Dashboard.
2. Go to Settings → Organization → Developers.
3. Click Create API key and copy the token.
4. Run:

mcpheroctl auth login --token <YOUR_ORG_TOKEN>

Verify

mcpheroctl auth status

The Wizard Pipeline

Follow this linear flow. After any async step, run scripts/poll.sh <server_id> to wait until the backend is idle.

1. create-session          → Returns server_id (save it, needed everywhere)
2. conversation (loop)     → Gather requirements; stop when is_ready: true
3. start                   → Transition to tool suggestion (async → poll)
4. list-tools              → Review AI-suggested tools
5. refine-tools (optional) → Iterate on tools until satisfied (async → poll)
6. submit-tools            → Confirm selection (deletes unselected tools)
7. (auto env var suggest)  → Triggered automatically after submit-tools (async → poll)
8. list-env-vars           → Review suggested env vars
9. refine-env-vars (opt.)  → Iterate on env vars (async → poll)
10. submit-env-vars        → Provide actual values (call even if list is empty — backend needs it to transition)
11. set-auth               → Generate bearer token for the server
12. generate-code          → Trigger code generation (async → poll)
13. deploy                 → Deploy to MCPHero runtime → returns server_url + bearer_token

Always call submit-env-vars, even when list-env-vars returns []. The backend requires this step to transition to the next state. With no env vars, just call it with no --var flags.

Full Wizard Example

Always use --json for scriptable output. Without it, human-friendly messages go to stderr and can confuse parsing.

# 1. Create session
mcpheroctl wizard create-session --json
# → {"server_id": "abc-123-..."}
SERVER_ID="abc-123-..."

# 2. Describe requirements (iterate until is_ready: true)
mcpheroctl wizard conversation $SERVER_ID --json \
  -m "I have a PostgreSQL database with customers and orders tables. I need tools to find customers by name, fetch orders for a customer, and get last hour's orders."
# Repeat with follow-up messages until output shows: "is_ready": true

# 3. Start tool suggestion (async)
mcpheroctl wizard start $SERVER_ID --json

# Poll until idle
scripts/poll.sh $SERVER_ID

# 4. Review tools (state should be "tools_selection")
mcpheroctl wizard list-tools $SERVER_ID --json

# 5. Refine if needed (async → poll again)
mcpheroctl wizard refine-tools $SERVER_ID --json \
  -f "Add error handling for missing customers. Rename get_customers_orders to get_orders_by_customer."
scripts/poll.sh $SERVER_ID

# 6. Submit selected tool IDs
mcpheroctl wizard submit-tools $SERVER_ID --json \
  --tool-id <tool-uuid-1> \
  --tool-id <tool-uuid-2> \
  --tool-id <tool-uuid-3>

# 7. Wait for env var suggestion (auto-triggered)
scripts/poll.sh $SERVER_ID

# 8. Review env vars
mcpheroctl wizard list-env-vars $SERVER_ID --json

# 9. Submit env var values (format: VAR_UUID=VALUE)
# ALWAYS call this even if list-env-vars returned [] — backend needs it to transition.
# With env vars:
mcpheroctl wizard submit-env-vars $SERVER_ID --json \
  --var "<env-var-uuid-1>=localhost" \
  --var "<env-var-uuid-2>=5432"
# Without env vars (empty list):
mcpheroctl wizard submit-env-vars $SERVER_ID --json

# 10. Set authentication
mcpheroctl wizard set-auth $SERVER_ID --json
# → {"bearer_token": "..."}  ← SAVE THIS

# 11. Generate code (async → poll)
mcpheroctl wizard generate-code $SERVER_ID --json
scripts/poll.sh $SERVER_ID

# 12. Deploy
mcpheroctl wizard deploy $SERVER_ID --json
# → {"server_url": "/mcp/<server-id>/mcp", "bearer_token": "...", "step": "complete"}

IMPORTANT: deploy returns a relative server_url like /mcp/<id>/mcp. Prepend the base domain to get the full URL:

https://api.mcphero.app/mcp/<server-id>/mcp

Server Management

mcpheroctl server list --json [CUSTOMER_ID]  # List all servers
mcpheroctl server get SERVER_ID --json       # Get server details + status
mcpheroctl server update SERVER_ID           # Update name/description
mcpheroctl server delete SERVER_ID --yes     # Delete (irreversible)
mcpheroctl server api-key SERVER_ID --json   # Retrieve bearer token

Connecting a Deployed Server to MCP Clients

After deploy, construct the full server URL:

https://api.mcphero.app{server_url}

Claude Desktop config

{
  "mcpServers": {
    "my-server": {
      "url": "https://api.mcphero.app/mcp/<server-id>/mcp",
      "headers": {
        "Authorization": "Bearer <bearer_token>"
      }
    }
  }
}

Config file locations:

• macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
• Windows: %APPDATA%\Claude\claude_desktop_config.json
• Linux: ~/.config/claude/claude_desktop_config.json

Gotchas

Free tier: Max 5 tools per server. wizard_submit_tools will error if more are selected.

Env var format in CLI: --var "UUID=VALUE" — the UUID is the env var's id from list-env-vars, not its name. Don't use the env var's display name.

Regenerate without redeploy: After using wizard_regenerate_tool_code, the code change takes effect immediately for already-deployed servers (the server auto-remounts).

Reference

• State machine: See references/state-machine.md for all setup_status values and which states are transient
• Exit codes: See references/exit-codes.md for mcpheroctl exit code meanings
• Polling script: Run scripts/poll.sh <server_id> to poll until idle (handles processing_status and processing_error automatically)