Social media posting from Zapier

Set it up with the Webhooks by Zapier → Custom Request

Webhooks by Zapier is not on Zapier’s Free plan; it needs Professional, Team or Enterprise. Zapier’s docs for this step.

1. 1

   Create an API key

   Start the trial, connect the accounts you want to post to, and create a key under API keys. It’s shown once. Store it in Zapier’s credentials rather than typing it into every step.

2. 2

   Find your account ids

   Add a Webhooks by Zapier → Custom Request step and run it once. Copy the id of each account from data; they stay the same even when an account is reconnected.

   List accounts: GET /v1/accounts

   Field	Value
   Method	GET
   URL	https://api.postpeg.com/v1/accounts
   Headers	Authorization | Bearer pp_live_your_key

3. 3

   Publish or schedule a post

   Add another Webhooks by Zapier → Custom Request step. Add "scheduled_at" (ISO 8601, e.g. 2026-10-01T09:00:00Z) to schedule instead of publishing now, and "media": [{ "url": "https://…", "type": "image" }] for images or video; Instagram, TikTok, YouTube and Pinterest need media.

   Create a post: POST /v1/posts

   Field	Value
   Method	POST
   URL	https://api.postpeg.com/v1/posts
   Data	The body below
   Headers	Authorization | Bearer pp_live_your_key Content-Type | application/json Idempotency-Key | (map the trigger item’s ID)

   BodyCopy JSON code

   {
     "account_ids": ["acc_mfz1x0k27d4q8vbn3c5s0a1p9e", "acc_mfz1y4r9h2c6t0wqk8e3m7ld5f"],
     "content": "(map the text here)"
   }

4. 4

   Check each account’s status

   The response is the post, with one target per account. Publishing happens in the background within seconds; GET /v1/posts/{id} later shows each target published with its url, or failed with the error.

   Response · 201 CreatedCopy 201 code

   {
     "id": "post_mfz2k3v8q1w5e9r4t7y0u2i6o3",
     "content": "Scheduled posts now retry on their own when a network has a bad minute. Changelog: https://example.com/changelog #buildinpublic",
     "media": [
       {
         "url": "https://example.com/changelog.png",
         "type": "image"
       }
     ],
     "platform_options": {},
     "status": "scheduled",
     "scheduled_at": "2026-10-01T09:00:00.000Z",
     "targets": [
       {
         "account_id": "acc_mfz1x0k27d4q8vbn3c5s0a1p9e",
         "platform": "x",
         "status": "pending",
         "platform_post_id": null,
         "url": null,
         "error": null,
         "attempts": 0,
         "published_at": null
       },
       {
         "account_id": "acc_mfz1y4r9h2c6t0wqk8e3m7ld5f",
         "platform": "linkedin",
         "status": "pending",
         "platform_post_id": null,
         "url": null,
         "error": null,
         "attempts": 0,
         "published_at": null
       },
       {
         "account_id": "acc_mfz20b5n1s8f4j7xv2p9r6hu1c",
         "platform": "instagram",
         "status": "pending",
         "platform_post_id": null,
         "url": null,
         "error": null,
         "attempts": 0,
         "published_at": null
       }
     ],
     "created_at": "2026-09-24T14:02:11.418Z"
   }

The postpeg app for Zapier

Errors and rate limits

Errors are JSON with a stable code and a detail written for people: route on the code, show the detail. The ones a workflow meets most:

400 invalid_request

The body, query or a platform rule is wrong. Read issues: it lists every problem with its path. Fix the request; retrying it unchanged fails the same way.

401 unauthorized

The key is missing, malformed or revoked. Send Authorization: Bearer pp_live_… with a key from the dashboard.

402 subscription_required

The trial or subscription has ended. Only GET /v1/me and /v1/billing still work: start a checkout to continue.

429 rate_limited

Too many requests, from your key or on the network’s side. Wait retry_after seconds (also in the Retry-After header), then retry.

502 upstream_error

The network failed or refused the request; detail carries its reason. Retry later if it didn’t respond; fix the request if it refused.

Each key can make 120 requests a minute, and at most 30 of them can be writes (publishing, scheduling, replying, sending, cancelling). A burst past that gets 429 rate_limited with Retry-After: 60: wait, then retry with the same idempotency key. Details in Authentication → Rate limits and Errors.