Environment variables not working in Cloudflare Workers / wrangler

Error text / 报错原文

• Environment variable is not defined
• binding not found
• vars ignored

What it means

A variable available in local dev is not available in the Worker runtime or production build.

Most common causes

• Local .env or .dev.vars is not deployed to production
• wrangler.toml vars differ by environment
• Secret was set in dashboard but not for the selected environment
• Build-time and runtime variables are confused

Fastest fix

• Check wrangler.toml and selected environment
• Set secrets with wrangler secret put
• Restart local dev after editing .dev.vars
• Log only variable presence, not values

Safe fix

• Maintain .env.example or .dev.vars.example
• Use environment-specific config blocks
• Validate required bindings at startup
• Keep production secrets out of source control

What not to do

• Do not commit .dev.vars with real secrets
• Do not assume Vite env variables exist at Worker runtime
• Do not print secret values in logs

How to confirm the fix

Run the smallest reproducible command first, then retry the agent task only after authentication, quota, and tool discovery are stable.

wrangler --version
wrangler secret list
wrangler deploy --dry-run

Related errors

• Rollup failed to resolve import - Vite / Vercel deployment →
• vite: not found / tsc: not found after NODE_ENV=production in Docker →
• You've hit your session limit / weekly limit - Claude Code →
• Prompt is too long - Claude Code context window →
• Not logged in - Please run /login - Claude Code →
• API Error: Repeated 529 Overloaded errors - Claude Code →

Related tools

• MCP Config Generator →
• JSON Formatter →
• Docker Compose Generator →
• JWT Decoder →
• Regex Tester →
• Hash Generator →
• URL Encoder →

Sources

Based on common developer troubleshooting patterns and linked EasyTool references.