Fathom Security Basics Skill

Fathom Security Basics

Overview

Fathom records and transcribes meetings, producing transcripts and action items that contain participant PII (names, emails, spoken content), confidential business decisions, and potentially sensitive negotiations. API keys are per-user and grant access to all meetings the user recorded or that were shared to their team. Protect recording consent workflows, transcript storage, and any analytics pipeline touching meeting content.

API Key Management

function createFathomClient(): { apiKey: string; baseUrl: string } {
  const apiKey = process.env.FATHOM_API_KEY;
  if (!apiKey) {
    throw new Error("Missing FATHOM_API_KEY — store in secrets manager, never in code");
  }
  // Fathom keys are per-user — never share across team members
  console.log("Fathom client initialized (key hash:", apiKey.slice(-4), ")");
  return { apiKey, baseUrl: "https://api.fathom.video/v1" };
}

Webhook Signature Verification

import crypto from "crypto";
import { Request, Response, NextFunction } from "express";

function verifyFathomWebhook(req: Request, res: Response, next: NextFunction): void {
  const signature = req.headers["x-fathom-signature"] as string;
  const secret = process.env.FATHOM_WEBHOOK_SECRET!;
  const expected = crypto.createHmac("sha256", secret).update(req.body).digest("hex");
  if (!signature || !crypto.timingSafeEqual(Buffer.from(signature), Buffer.from(expected))) {
    res.status(401).send("Invalid signature");
    return;
  }
  next();
}

Input Validation

import { z } from "zod";

const MeetingQuerySchema = z.object({
  meeting_id: z.string().uuid(),
  include_transcript: z.boolean().default(false),
  date_from: z.string().regex(/^\d{4}-\d{2}-\d{2}$/).optional(),
  date_to: z.string().regex(/^\d{4}-\d{2}-\d{2}$/).optional(),
  participant_email: z.string().email().optional(),
});

function validateMeetingQuery(data: unknown) {
  return MeetingQuerySchema.parse(data);
}

Data Protection

const FATHOM_PII_FIELDS = ["participant_email", "participant_name", "phone_number", "transcript_text"];

function redactFathomLog(record: Record<string, unknown>): Record<string, unknown> {
  const redacted = { ...record };
  for (const field of FATHOM_PII_FIELDS) {
    if (field in redacted) redacted[field] = "[REDACTED]";
  }
  // Also scrub emails from transcript snippets
  if (typeof redacted.summary === "string") {
    redacted.summary = (redacted.summary as string).replace(/[\w.+-]+@[\w-]+\.[\w.-]+/g, "[REDACTED_EMAIL]");
  }
  return redacted;
}

Security Checklist

[ ] API key stored in secrets manager, never in code
[ ] Meeting recordings and transcripts encrypted at rest
[ ] PII redacted in non-production environments
[ ] Webhook endpoints use HTTPS with signature verification
[ ] Access logs track per-user API key usage
[ ] Recording consent verified before processing transcripts
[ ] Transcript data retention policy enforced
[ ] Action items containing confidential terms scrubbed before export

Error Handling

| Vulnerability | Risk | Mitigation | |---|---|---| | Leaked API key | Access to all user meetings and transcripts | Secrets manager + key regeneration | | Unredacted transcripts in logs | Participant PII exposure | Field-level redaction pipeline | | Missing recording consent | Legal liability under two-party consent laws | Consent verification before processing | | Unencrypted transcript storage | Bulk meeting data breach | Encryption at rest + access controls | | Overly broad meeting sharing | Confidential content exposed to wrong teams | Per-meeting permission scoping |

Resources

Next Steps

See fathom-prod-checklist.

Agent Skills: Fathom Security Basics

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