otp.com in Codex

Add an otp.com section to AGENTS.md and Codex reads the integration steps as project instructions, then writes the send and verify calls into your code.

Get Your API Key Free
curl -fsSL https://otp.com/ai/files/codex/otp-agents-section.md >> AGENTS.md
Codex
Ready
  1. Read AGENTS.md ## otp.com OTP verification
  2. Read the API key OTP_API_KEY · server env
  3. Added the send call
    SMSWhatsAppTelegramEmail
  4. Added the verify call POST /otp/verify
Add otp.com phone verification to the signup flow.
Codex · AGENTS.md

Set up otp.com in Codex

Create an API key in the panel (API Keys). Start with an otp_test_ key. Append the section to AGENTS.md with the command below, or download it and paste it into AGENTS.md at the repo root. Ask for the integration. The agent writes the send and verify calls into your code, with the key read from OTP_API_KEY on the server.

curl -fsSL https://otp.com/ai/files/codex/otp-agents-section.md >> AGENTS.md
Download otp-agents-section.md

Append this section to AGENTS.md at the repo root (the download is the section only, so it does not replace your file). Codex reads AGENTS.md for project instructions.

What to ask once the file is in place

my-app · codex · 80×24
james@macmy-app% codex
> Add phone verification to sign-up with otp.com: send a code when the user submits their number, then verify it.
● Reading AGENTS.md
● Editing src/auth/signup.ts
✓ Send and verify calls added
EXAMPLE PROMPT

Add phone verification to sign-up with otp.com: send a code when the user submits their number, then verify it.

my-app · codex · 80×24
james@macmy-app% codex
> Read https://otp.com/ai/prompt.md and integrate otp.com OTP verification into this project.
● Fetching otp.com/ai/prompt.md
● Step 1: POST /otp/send
✓ Step 2: POST /otp/verify wired in
OR POINT IT AT THE FILE

Read https://otp.com/ai/prompt.md and integrate otp.com OTP verification into this project.

Full integration prompt as Markdown →

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Frequently Asked Questions

Is my API key safe?

Keep the key in an environment variable or a secret on your server (OTP_API_KEY), never in the rules file or the prompt, and never commit it. Use a test key (otp_test_) while you build.

Does the agent see the code?

No. The API never returns the code. The user receives it on their phone or in their inbox, and your app verifies what they type against the otp_id from the send call.

Can I test without sending real messages?

Yes. A test key (otp_test_) runs in the sandbox: send returns a real otp_id and a pending status, but nothing is delivered and nothing is charged. Verify accepts the fixed code 123456 on the default 6-digit length.

How is it billed?

Per verification sent: one charge per code, at the published per-country rate. Verifying is free, and a resend counts as a new verification. Test keys are never charged.