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+# TaxonRouter Environment Variables
+#
+# Copy to .env and fill in your values.
+# NEVER commit .env to version control.
+
+# GitHub API Token (required)
+# Generate at: https://github.com/settings/tokens
+# Required scopes: repo (for private repos), read:user
+GITHUB_TOKEN=
+
+# GitHub App credentials (for auto-tagger)
+# If using GitHub App authentication instead of token
+GITHUB_APP_ID=
+GITHUB_APP_PRIVATE_KEY=
+
+# LLM Provider (required for classification)
+# Options: openai, anthropic, azure-openai, local
+LLM_PROVIDER=anthropic
+LLM_API_KEY=
+LLM_MODEL=claude-sonnet-4-20250514
+LLM_BASE_URL=
+
+# Webhook secret (verify incoming payloads)
+WEBHOOK_SECRET=
+
+# MCP Server
+MCP_SERVER_PORT=3000
+
+# Auto-tagger
+AUTO_TAGGER_PORT=3001
+AUTO_TAGGER_LOG_LEVEL=info