Transports

Stdio

• Best for desktop assistants; avoids base64 limits
• Prefer filePath for fidelity

HTTP (streamable)

• Node implementation at /mcp
• JSON body size limit ~16 MB
• Use API key for Faxbot REST calls from tools via environment (API_KEY)

SSE + OAuth2

• Node and Python servers require Bearer JWT with issuer/audience and JWKS
• Configure: OAUTH_ISSUER, OAUTH_AUDIENCE, optional OAUTH_JWKS_URL
• Always run behind TLS

Limits

• REST API raw file limit: MAX_FILE_SIZE_MB (default 10 MB)
• Node MCP JSON body limit: ~16 MB base64 payload