Add MCP Vercel

Add Vercel MCP Plugin

Step 0: Language selection

Before proceeding with any other steps in this skill, ask the user which language to continue in using AskUserQuestion. Keep this initial prompt in English because the preferred language is not yet known.

• Question: Which language should I continue in?
• Options: English, 日本語 (Japanese)

Use the selected language for all subsequent user-facing messages and for every further AskUserQuestion prompt in this skill. Do not translate code, file paths, shell commands, or file contents.

This skill configures the Vercel MCP plugin so container agents can deploy websites, manage projects, and list deployments.

UX Note: Use AskUserQuestion for all user-facing questions.

Phase 1: Pre-flight

Check if already configured

grep -c "VERCEL_API_TOKEN" .env 2>/dev/null || echo "0"

If token exists, ask user: keep existing or reconfigure?

Check deploy/{ASSISTANT_NAME}/host/entry.ts has Vercel registration

Read deploy/{ASSISTANT_NAME}/host/entry.ts and verify it contains registerMcpPlugin("vercel". If not, add it.

Phase 2: Get API Token

AskUserQuestion: Do you already have a Vercel API token?

If no — guide through creation:

1. Go to https://vercel.com/account/tokens
2. Click Create token
3. Name: nagi (or any name)
4. Scope: Full Account (or specific project)
5. Copy the token

Configure .env

Add to .env:

VERCEL_API_TOKEN=...

Phase 3: Configure entry.ts

Verify deploy/{ASSISTANT_NAME}/host/entry.ts contains the Vercel MCP plugin registration. If not, add this block after the orchestrator creation:

const vercelEnv = readEnvFile(["VERCEL_API_TOKEN"]);
if (vercelEnv.VERCEL_API_TOKEN) {
  orchestrator.registerMcpPlugin("vercel", {
    entryPoint: "/app/mcp-plugins/vercel/dist/index.js",
    env: { VERCEL_API_TOKEN: vercelEnv.VERCEL_API_TOKEN },
  });
  logger.info("Vercel MCP plugin registered");
}

If deploy/{ASSISTANT_NAME}/host/entry.ts is outdated, compare with deploy/templates/host/entry.template.ts and update accordingly.

Phase 4: Rebuild & Verify

Rebuild Docker image (if not already built with Vercel plugin)

./container/claude-code/build.sh

Restart nagi

pnpm dev

Test

Tell user:

Send a message in your Slack channel asking the agent to deploy something:

• "Deploy a simple hello world page to Vercel"
• "List my Vercel projects"

The agent should use mcp__vercel__vercel_deploy or mcp__vercel__vercel_list_projects.

Available Tools

Once configured, container agents have access to:

• vercel_list_projects — List Vercel projects
• vercel_create_project — Create a new project
• vercel_deploy — Deploy files and get a URL
• vercel_list_deployments — List recent deployments
• vercel_get_deployment — Get deployment details
• vercel_delete_project — Delete a project

Troubleshooting

"VERCEL_API_TOKEN is not set"

The token must be in .env at the project root AND registered in deploy/{ASSISTANT_NAME}/host/entry.ts via registerMcpPlugin with env: { VERCEL_API_TOKEN: ... }.

Agent doesn't see Vercel tools

1. Check deploy/{ASSISTANT_NAME}/host/entry.ts has registerMcpPlugin("vercel", ...)
2. Check Docker image was rebuilt after adding the plugin: ./container/claude-code/build.sh
3. Restart nagi after changes

Deploy fails

1. Verify token is valid: curl -s -H "Authorization: Bearer $VERCEL_API_TOKEN" https://api.vercel.com/v9/projects | head
2. Check token scope has deploy permissions