Elevenlabs Webhooks Events

What it does

When your agent uses it

• Setting up webhook endpoints for transcription completion
• Agent conversation events from ElevenLabs
• With elevenlabs webhook
• Elevenlabs events

Example prompts

• “elevenlabs webhook”
• “elevenlabs events”
• “elevenlabs webhook signature”
• “/elevenlabs-webhooks-events”

Requirements

• Compatibility (from SKILL.md): Designed for Claude Code
• Pre-approved tools (allowed-tools): Read, Write, Edit, Bash(curl:*)

Workflow steps

7 steps, taken from the first numbered list in SKILL.md.

1. 1Know the event types — subscribe only to what you handle (table below).
2. 2Create the webhook in the dashboard (Settings > Webhooks) and copy the HMAC secret.
3. 3Verify the signature with HMAC-SHA256 over ".", using a timing-safe compare and a 5-minute replay window. See the full verifier.
4. 4Handle the request with a raw body parser, ack 200 immediately, then process asynchronously. See the Express handler.
5. 5Route events to per-type handlers. See handler examples.
6. 6Guard against duplicates with idempotency keyed on the event ID. See idempotency.
7. 7Test locally by tunneling with ngrok. See local testing.

What it can do on your machine

Read from SKILL.md and the folder at commit cfae287. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves these tools, so the agent can use them without asking each time:

  • Read
  • Write
  • Edit
  • Bash(curl:*)

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Shell commands in SKILL.md call:

  • curl

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Links to these hosts (documentation or services it may open):

  • elevenlabs.io

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names no API keys, tokens, secrets or passwords.

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

• Compatibility

  Designed for Claude Code

  From compatibility in the SKILL.md frontmatter.

Context cost

Elevenlabs Webhooks Events loads about 1.8k tokens when it runs, and up to ~3.5k if it reads all its reference files. Until then it costs about 106 tokens; SKILL.md has 522 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~106

When it runs · the whole SKILL.md, loaded when a task matches

~1.8k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~3.5k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from jeremylongshore/tons-of-skills-marketplace at commit cfae287, republished under its MIT licence (© jeremylongshore). 522 words, ~1,758 tokens.

name

elevenlabs-webhooks-events

description

Implement ElevenLabs webhook HMAC signature verification and event handling. Use when setting up webhook endpoints for transcription completion, call recording, or agent conversation events from ElevenLabs. Trigger with "elevenlabs webhook", "elevenlabs events", "elevenlabs webhook signature", "handle elevenlabs notifications", "elevenlabs post-call webhook", "elevenlabs transcription webhook".

allowed-tools

Read, Write, Edit, Bash(curl:*)

compatibility

Designed for Claude Code

version

1.6.0

license

MIT

author

Jeremy Longshore <jeremy@intentsolutions.io>

tags

saas, voice, ai, elevenlabs, webhooks, events

// src/elevenlabs/webhook-verify.ts — Header: t=<unix_ts>,v1=<hex_sig>
export function verifyWebhookSignature(rawBody, signatureHeader, secret) {
  const parts = new Map(signatureHeader.split(",").map(p => {
    const [k, ...v] = p.split("="); return [k, v.join("=")];
  }));
  const timestamp = parts.get("t"), signature = parts.get("v1");
  if (Math.floor(Date.now() / 1000) - parseInt(timestamp) > 300) {
    return { valid: false, reason: "Timestamp too old" };   // replay guard
  }
  const expected = crypto.createHmac("sha256", secret)
    .update(`${timestamp}.${rawBody.toString()}`).digest("hex");
  return { valid: crypto.timingSafeEqual(
    Buffer.from(signature, "hex"), Buffer.from(expected, "hex")) };
}

switch (event.type || event.event_type) {
  case "post_call_transcription": await handleTranscription(event); break;
  case "post_call_audio":         await handleCallAudio(event);     break;
  case "call_initiation_failure": await handleCallFailure(event);   break;
  case "speech_to_text.completed": await handleSTTCompleted(event); break;
  default: console.log("Unhandled event type:", event.type);
}

curl -X POST http://localhost:3000/webhooks/elevenlabs \
  -H "Content-Type: application/json" \
  -H "ElevenLabs-Signature: t=$(date +%s),v1=test" \
  -d '{"type":"speech_to_text.completed","data":{"text":"Hello world"}}'

© jeremylongshore, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 2 other files (references) in skills/.curated/elevenlabs-webhooks-events of jeremylongshore/tons-of-skills-marketplace.

• SKILL.md
• references/examples.md
• references/implementation.md

Open the folder on GitHubat commit cfae287