Which keyword do I set?

FishOut — exactly that. Every message FishOut sends to Feishu or Lark has “FishOut · ” at the start of the card title, so the keyword check always passes.

Can I use signature verification instead?

Not today. The signature secret is not part of the webhook URL, and FishOut does not sign for Feishu. With signing on, every alert is refused with 19021, and delivery history shows feishu_signature_required.

Does it work with Lark as well as Feishu?

Yes. Lark’s custom bot URL is on open.larksuite.com and Feishu’s on open.feishu.cn; FishOut accepts both, and the card is the same.

Is the content translated?

No. Post titles stay in the language they were written in. Our own words in the card are English.

IntegrationsWorkplace chat

Brand mentions in a Feishu or Lark group

Feishu, and Lark outside China, take a custom bot webhook in a couple of clicks. The bot’s security settings are where setups fail: a keyword the message does not contain is refused, and the refusal arrives as a code in the response body.

Start free Read the alerts docs

Every alert channel is on every plan, including Free.

[01] WHAT LANDS THERE/ A GROUP

A mention, as it arrives in Feishu / Lark

Rendered by the code that sends it, from a sample Hacker News post. Never the post body.

群 · Brand watch

FishOut botBotnow

FishOut · Reply now: a relevant post on Hacker News

Ask HN: How do small teams handle support email without a helpdesk?

Relevance 92 · Topic · Neutral · by mirelle

Hint: Answer the question directly

Labels: Question, Asking for recommendations

Open in FishOutView on Hacker News

[02] CONNECT IT/ SETUP

Point FishOut at a group

3 steps, a few minutes end to end.

1
Add a custom bot to the group
In the group’s settings, open Bots → Add bot → Custom bot. Give it a name and avatar, then copy the webhook URL it shows.
feishu url (lark: open.larksuite.com)
```
https://open.feishu.cn/open-apis/bot/v2/hook/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
```
2
Set the custom keyword to FishOut
Under the bot’s security settings, add the keyword FishOut. Every FishOut message contains it in the card title, so the check passes. FishOut does not sign requests for Feishu, so leave signature verification off, and do not add an IP allowlist.
3
Paste the URL into FishOut
Under Settings → Notifications, add a Feishu / Lark channel and paste it. Both hosts are accepted: open.feishu.cn and open.larksuite.com.

Then set the floor

A Feishu group is usually a working team’s group, not a dedicated alerts channel, so every card lands between real conversations. Keep the floor at 80 or above and let the green Reply now header do the triage at a glance: green is worth opening now, blue can wait.

Settings · Notifications

Feishu / Lark

https://open.feishu.cn/…

Healthy

Relevance floor80

Eventsmention.scored

Batch bursts5 min

[03] WHAT IS IN IT/ FIELDS

What Feishu / Lark receives, field by field

Built from the event’s envelope and nothing else, so a retry renders exactly the message the first attempt would have.

Field		How
Card header	Shown	“FishOut · ” plus the headline; green for Reply now, blue otherwise.
Post title	Clipped	plain_text only, clipped at 200 characters — never lark_md, so markup cannot become @all.
Relevance, subject, sentiment, author	Shown	Its own plain_text row.
Reply hint and labels	Shown	plain_text rows.
Buttons	Shown	Open in FishOut (primary) and View on the platform.
Post body	Never	Never sent: the envelope does not carry it.

[04] TEN PINGS OR ONE/ DIGEST

A burst arrives as one message

Feishu / Lark batches by default. Here 3 posts were held after the first; they arrive together when the window closes, best first.

群 · Brand watch · 5-min digest

FishOut botBot+5m

FishOut · 3 new mentions for AcmeMail

Ask HN: Tools for a support team across time zones? · Hacker News · 89
AcmeMail API is the best-documented in the category · Hacker News · 82
Shared inboxes are the new helpdesks · Hacker News · 76

Open in FishOut

[05] WHAT WILL BITE YOU/ LIMITS

Feishu’s limits, not ours

These are Feishu’s and Lark’s constraints, checked against the custom bot guide on both open platforms. Failures are tracked per channel, so one broken destination never stops the others.

A custom bot can be protected with custom keywords (up to 10), an IP allowlist and a signature, in any combination. FishOut works with the keyword setting. [source]

Each bot is limited to 100 requests a minute and 5 a second per tenant, and Feishu advises avoiding sends on the hour and half hour, when 11232 throttling is likeliest. [source]

A request body may not exceed 20 KB. A FishOut card is well under, because it never carries the post body. [source]

Failures come back as a code in the JSON body (19024, 19021, 9499…), so FishOut reads the body before it records a delivery, rather than trusting the status alone. [source]

In the channel’s delivery history
You see	It means	Do this
feishu_keyword_mismatch	Code 19024: the bot’s keyword is not FishOut.	Set the custom keyword to FishOut.
feishu_signature_required	Code 19021: signature verification is switched on.	Turn signing off and use the keyword instead.
feishu_ip_not_allowed	Code 19022: an IP allowlist is set.	Remove the allowlist; FishOut has no fixed sending addresses.
feishu_rate_limited	Code 11232: throttled. Retried after 60 seconds.	Nothing, usually; batching keeps bursts small.