Who enters which code

Which person or program enters each Envoy credential, where it may go, and what to do when your host forbids entering a code.

Read this page before you build or run an agent that handles sign-in, one-time codes or card details. Each credential has one owner and one destination. An Envoy tool never receives a bank code.

Support revision: envoy@2026-10. Last updated: 28 October 2026.

Who enters what

Credential	Who enters it	Where it may go	Host-policy caveat	Keep it?
Envoy sign-in (app request or SMS code)	The user approves in the Envoy app. For an SMS code, the user reads the 6-digit code to the agent, and the agent types it once.	The Envoy sign-in page at `https://envoy.money/agent-login`. With hosted MCP, the user signs in on Envoy's page in the window the host opens.	Some hosts forbid typing a code. Then the user types it.	No
OAuth access and refresh tokens	The client, not the user.	The client's private storage only.	None recorded.	Yes, in private storage only
Merchant or Instinct vault sign-in code (`needs_answer`, kind `otp`)	The user gives the code named by Envoy's open question. The agent sends it once.	`submit_answer`, only for that exact question.	Some hosts forbid passing a code. Then stop and hand the step to the user.	No
Merchant password (never passes through chat)	Nobody. Envoy never asks for a password, and the agent never asks the user for one.	Nowhere. When the merchant wants one, the reply says so; the user can cancel and buy on the merchant site.	None.	No
Bank or payment OTP on Envoy checkout	The user, in the Envoy app. On agent checkout the bank's code is the `checkout_code` below.	The Envoy app (`enter_otp`). Never the agent, chat or an Envoy tool.	The agent does not ask for or enter this code.	No
`checkout_code`	The agent.	The bank page's code or OTP box for this card, once. It is the card's OTP.	The bank can reject it; do not retry.	No
Card details	The agent, on the merchant page.	The merchant's payment form, from an authorized `ready` reply.	Follow the connected host's profile.	No
Gift-card code and PIN	The agent only when the ready reply instructs redemption.	This purchase's merchant gift-card form. Envoy can instead complete checkout without releasing them.	Follow the connected host's profile.	No

A checkout_code is optional and exists only on the card route. It can be absent. A gift-card payment link is for the user to open and pay; it is not a credential or an approval link.

Agent checkout and Envoy checkout differ

On agent checkout, the agent pays on the merchant page with the one-time card. If the bank page asks for a code or OTP, enter the returned checkout_code there once: it is the card's OTP. The bank sends the user no code for this card, so never ask the user for one. If the bank rejects the code, do not retry; report failed with failure_reason otp_failed.

On Envoy checkout, Envoy pays in its own browser. The user enters any bank code in the Envoy app. The agent has nothing to enter.

Not every charge needs a bank code. Do not tell the user to expect one.

If your host forbids entering a code

Stop at that step.
Tell the user which page needs a code.
Hand the step to the user, who completes it.
Do not look for another way. A workaround can expose the code or break your host's rules.

Never

Never put real secrets in examples, logs, memory or files.
Never paste a bank or payment OTP, a token or a callback URL into chat. Send a merchant or Instinct vault sign-in code only when Envoy's exact open otp question requests it; send it once with submit_answer, and never repeat or retain it.
Never send a bank code to submit_answer. Send only a merchant or Instinct vault sign-in code that Envoy's open otp question requests.
Never ask the user for a merchant password. Envoy never takes a password through chat.

Where to go next

Browser agents for the sign-in steps in a browser.
Connect over MCP for hosted sign-in and tokens.
Purchase walkthrough for the full flow, including ready and report_checkout_result.
API security for token and log handling.

You succeed when no card, checkout code or voucher secret appears in agent replies or retained records. Send a merchant sign-in answer only to its exact open question. If a step stalls, hand it to the user and follow the recovery steps in the walkthrough.