Discord Webhook Sender

A webhook URL contains an ID and a token: `https://discord.com/api/webhooks/{id}/{token}`. Anyone holding that URL can post to the channel it belongs to, with no authentication beyond the token itself. There is no account, no permission check and no rate-limit tied to a user.

That makes a leaked webhook URL a spam vector. Committing one to a public repository is a well-known way to have a channel flooded within hours by bots that scrape GitHub for exactly this pattern. If a URL leaks, delete the webhook in channel settings - regenerating is not possible, and rotating means creating a new one and updating whatever uses it.

Webhooks cannot read messages, join voice, or do anything except post to their own channel. That limited scope is why they are safe to hand to a CI pipeline or a monitoring service in a way a bot token never would be.

Discord enforces per-field character limits and a combined ceiling. Title is 256 characters, description 4096, field name 256, field value 1024, footer text 2048 and author name 256. You may send up to 10 embeds per message and 25 fields per embed.

The limit people hit unexpectedly is the aggregate one: the sum of all title, description, field name, field value, footer and author text across every embed in a single message cannot exceed 6000 characters. A message with ten individually-valid embeds can still be rejected on the total.

Exceeding a limit returns HTTP 400 with a JSON body naming the offending field. If your webhook silently does nothing, read the response body - the error is almost always specific about which field is too long.

Keep the title short and descriptive. Use fields for structured data like event dates or leaderboard entries. Choose a color that matches your server brand, and fill in the footer with the source or timestamp for context.

Images and thumbnails should be hosted on HTTPS. Discord will not display images served over plain HTTP.

Webhooks can send up to 30 messages per second per channel. Each message body must stay under 8 MB including files. For automated workflows, structure your code so that a temporary webhook failure does not break your entire system.