# Construct a narrow

A **narrow** is a set of filters for Zulip messages, that can be based
on many different factors (like sender, channel, topic, search
keywords, etc.). Narrows are used in various places in the Zulip
API (most importantly, in the API for fetching messages).

It is simplest to explain the algorithm for encoding a search as a
narrow using a single example. Consider the following search query
(written as it would be entered in the Zulip web app's search box).
It filters for messages sent to channel `announce`, not sent by
`iago@zulip.com`, and containing the words `cool` and `sunglasses`:

```
channel:announce -sender:iago@zulip.com cool sunglasses
```

This query would be JSON-encoded for use in the Zulip API using JSON
as a list of simple objects, as follows:

```json
[
    {
        "operator": "channel",
        "operand": "announce"
    },
    {
        "operator": "sender",
        "operand": "iago@zulip.com",
        "negated": true
    },
    {
        "operator": "search",
        "operand": "cool sunglasses"
    }
]
```

The Zulip help center article on [searching for messages](/help/search-for-messages)
documents the majority of the search/narrow options supported by the
Zulip API.

Note that many narrows, including all that lack a `channel` or `channels`
operator, search the current user's personal message history. See
[searching shared history](/help/search-for-messages#searching-shared-history)
for details.

Clients should note that the `is:unread` filter takes advantage of the
fact that there is a database index for unread messages, which can be an
important optimization when fetching messages in certain cases (e.g.,
when [adding the `read` flag to a user's personal
messages](/api/update-message-flags-for-narrow)).

**Changes**: In Zulip 9.0 (feature level 271), narrows gained support
for a new `with` operator for linking to topics.

In Zulip 9.0 (feature level 265), support was added for a
new `is:followed` filter, matching messages in topics that the current
user is [following](/help/follow-a-topic).

In Zulip 9.0 (feature level 250), support was added for
two filters related to stream messages: `channel` and `channels`. The
`channel` operator is an alias for the `stream` operator. The `channels`
operator is an alias for the `streams` operator. Both `channel` and
`channels` return the same exact results as `stream` and `streams`
respectively.

In Zulip 9.0 (feature level 249), support was added for a new filter,
`has:reaction`, which returns messages that have at least one [emoji
reaction](/help/emoji-reactions).

In Zulip 7.0 (feature level 177), support was added
for three filters related to direct messages: `is:dm`, `dm` and
`dm-including`. The `dm` operator replaced and deprecated the
`pm-with` operator. The `is:dm` filter replaced and deprecated
the `is:private` filter. The `dm-including` operator replaced and
deprecated the `group-pm-with` operator.

The `dm-including` and `group-pm-with` operators return slightly
different results. For example, `dm-including:1234` returns all
direct messages (1-on-1 and group) that include the current user
and the user with the unique user ID of `1234`. On the other hand,
`group-pm-with:1234` returned only group direct messages that included
the current user and the user with the unique user ID of `1234`.

Both `dm` and `is:dm` are aliases of `pm-with` and `is:private`
respectively, and return the same exact results that the deprecated
filters did.

## Narrows that use IDs

### Message IDs

The `with` operator is designed to be used in links that should follow
a topic across being moved. Its operand is a message ID.

The `near` and `id` operators, documented in the help center,
also use message IDs for their operands.

* `with:12345`: Search for the conversation (stream/topic pair) which
  contains the message with ID `12345`. If such a message exists, and
  can be accessed by the user, then the search will be treated as having
  the `channel`/`topic`/`dm` operators corresponding to the
  conversation containing that message, replacing any such operators
  in the original request.
* `near:12345`: Search messages around the message with ID `12345`.
* `id:12345`: Search for only message with ID `12345`.

The message ID operand for the `with` and `id` operators may be encoded
as either a number or a string. The message ID operand for the `near`
operator must be encoded as a string.

**Changes**: Prior to Zulip 8.0 (feature level 194), the message ID
operand for the `id` operator needed to be encoded as a string.


```json
[
    {
        "operator": "id",
        "operand": 12345
    }
]
```

### Channel and user IDs

There are a few additional narrow/search options (new in Zulip 2.1)
that use either channel IDs or user IDs that are not documented in the
help center because they are primarily useful to API clients:

* `channel:1234`: Search messages sent to the channel with ID `1234`.
* `sender:1234`: Search messages sent by user ID `1234`.
* `dm:1234`: Search the direct message conversation between
  you and user ID `1234`.
* `dm:1234,5678`: Search the direct message conversation between
  you, user ID `1234`, and user ID `5678`.
* `dm-including:1234`: Search all direct messages (1-on-1 and group)
  that include you and user ID `1234`.

!!! tip ""

    A user ID can be found by [viewing a user's profile][view-profile]
    in the web or desktop apps. A channel ID can be found when [browsing
    channels][browse-channels] in the web or desktop apps.

The operands for these search options must be encoded either as an
integer ID or a JSON list of integer IDs. For example, to query
messages sent by a user 1234 to a direct message thread with yourself,
user 1234, and user 5678, the correct JSON-encoded query is:

```json
[
    {
        "operator": "dm",
        "operand": [1234, 5678]
    },
    {
        "operator": "sender",
        "operand": 1234
    }
]
```

[view-profile]: /help/view-someones-profile
[browse-channels]: /help/introduction-to-channels#browse-and-subscribe-to-channels