# Filtering published\_at yields "Request not understood error, cannot list posts."

**URL:** <https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762>\
**Category:** Developer help\
**Created:** [May 26, 2025, 9:50am UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762 "2025-05-26T09:50:19Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![Heaney555](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.ghost.org/heaney555/32/30944_2.png) [@Heaney555](https://forum.ghost.org/u/Heaney555)\
**Post date:** [May 26, 2025, 9:50am UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762/1 "2025-05-26T09:50:19Z")

</div>

Hi there.

We use Ghost(Pro), and we’ve been using the following query with the Ghost Content API for many months now:

`https://uploadvr.ghost.io/ghost/api/content/posts/?key=[KEY]&filter=primary_author:[NAME]+published_at:>='2025-05-18'`

(above, I’ve replaced the actual key and primary\_author with square brackets, and used an example date)

**This has worked for many months with no issues - until the past few days.**

Suddenly, it is yielding:  
`{"errors":[{"message":"Request not understood error, cannot list posts.","context":"Error parsing filter","type":"BadRequestError","details":null,"property":null,"help":null,"code":null`

It’s definitely published\_at causing this, since if I remove that the error goes away.

Is this a regression, or a change to the API? What’s going on here?

---

<div class="post-metadata">

**Author:** ![Cathy\_Sarisky](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.ghost.org/cathy_sarisky/32/25750_2.png) [@Cathy\_Sarisky](https://forum.ghost.org/u/Cathy_Sarisky)\
**Post date:** [May 26, 2025, 11:36am UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762/2 "2025-05-26T11:36:35Z")

</div>

If you remember primary\_author, does it work correctly?  
Are you URL encoding your strings for the filter?

---

<div class="post-metadata">

**Author:** ![Cathy\_Sarisky](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.ghost.org/cathy_sarisky/32/25750_2.png) [@Cathy\_Sarisky](https://forum.ghost.org/u/Cathy_Sarisky)\
**Post date:** [May 26, 2025, 11:46am UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762/3 "2025-05-26T11:46:10Z")

</div>

Just tried on Ghost Pro.

My ‘raw’ string is: `filter=primary_author:cathy+published_at:>'2025-05-18'`

After encoding, I have:  
`https://cathys-second-demo-site.ghost.io/ghost/api/content/posts/?key=fe271d7637c1e685bc13e11f21&filter=primary_author%3Acathy%2Bpublished_at%3A%3E%272025-05-18%27 `, which works fine. I’m test on Ghost Pro, which is 5.120.1-0-ge3b36eb+moya for my site today.

---

<div class="post-metadata">

**Author:** ![Heaney555](https://sea1.discourse-cdn.com/flex015/user_avatar/forum.ghost.org/heaney555/32/30944_2.png) [@Heaney555](https://forum.ghost.org/u/Heaney555)\
**Post date:** [May 26, 2025, 12:22pm UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762/4 "2025-05-26T12:22:56Z")

</div>

On further testing, this seems to only happen in Zapier WebRequest steps, and as you note, it works fine if done elsewhere.

Either something has changed with how Ghost handles URL/query decoding or something has changed with how Zapier encodes.

Regardless, I can workaround by using raw requests of my own.

---

<div class="post-metadata">

**Author:** ![system](https://us1.discourse-cdn.com/flex015/uploads/ghost2/original/2X/b/ba9ce5100b8bb264586f4f572545596b2ce3f081.png) [@system](https://forum.ghost.org/u/system)\
**Post date:** [August 24, 2025, 12:23pm UTC](https://forum.ghost.org/t/filtering-published-at-yields-request-not-understood-error-cannot-list-posts/57762/5 "2025-08-24T12:23:27Z")

</div>

This topic was automatically closed 90 days after the last reply. New replies are no longer allowed.