> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apostra.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Identify a Message Sender
> Record who an observed email sender is, without granting that person any access
## Overview
When someone emails an Apostra inbox, Apostra keeps the message as a Session —
a durable conversation and its working context — before anyone knows who wrote
it. The sender is retained as an **observation**: the address Apostra saw on
the envelope. An observation carries no account membership, no verified
identity, and no permission to act.
Account admins can say who that observed sender is. A decision names a
customer, an advertiser, or a user, and Apostra keeps it as a dated, attributed
record of how the conclusion was reached.
Identifying a sender resolves **who they are**. It does not grant access, move
the conversation into an account, change who can read it, or act on anything
the sender asked for earlier. Claiming a conversation and granting account
access are separate, separately authorized operations.
## What you can see
Your admins see senders observed on Sessions that belong to **your own
account**. A message that reached a shared Apostra inbox rather than your
account's inbox belongs to that receiving integration and is not visible to any
customer; only Apostra operators can identify those senders.
Each entry shows the transport the message arrived on, the observed address,
the display name when the message carried one, when the sender was first and
last observed, how many messages Apostra has seen from them, and every link
decision that currently stands.
Filter by `unresolved` to see only senders with no standing confirmed link —
the queue of people still to identify.
## Recording a decision
A decision has a state and a target.
**States**
* `candidate` — a proposed identification that nobody has confirmed. Several
candidates can stand at once.
* `confirmed` — the standing answer.
* `rejected` — this target is not who the sender is.
* `revoked` — a previously confirmed link that no longer holds.
**Targets**
* `customer` — the account the sender belongs to.
* `advertiser` — one of that customer's advertisers.
* `principal` — a user who is a member of that customer.
### Rules that apply
* **You must be an account admin.** Other members cannot see the list or record
a decision.
* **Identify the customer first.** On a shared-inbox Session, an advertiser or
user cannot be linked until a customer is confirmed for that sender. On your
own account's Session the customer is already your account, and naming a
different one is refused.
* **One customer at a time.** A sender can carry several candidate customers,
but only one confirmed one. Revoke or reject the standing confirmation before
confirming a different customer.
* **The target must be real and related.** The advertiser must belong to that
customer and not be archived; the user must hold an active membership of it.
* **Decisions are never edited.** Changing your mind records a new decision
that supersedes the previous one. The earlier decision stays readable and is
reported as `superseded`.
* **Evidence is chosen by Apostra, not by you.** Each decision is bound to a
retained message in that conversation, so a later conclusion can never appear
to have been known to an earlier message.
* **Record decisions as yourself.** A decision made while impersonating another
user is refused, because the record names the person who made it for as long
as it is kept.
Send a `clientRequestId` you generate with each decision. Repeating it returns
the original decision unchanged, so a retried request never records a second
conclusion.
## Availability
This is an early capability, enabled per account. Email intake is not yet
generally available, so most accounts will have no observed senders to
identify. Contact your Apostra representative if you want your account enrolled.
## Related
The same access model for people observed in a connected support channel.
Definitions for advertiser, principal, and account membership.
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