Hey Piotr, I’ve run into this exact issue before—let’s walk through how to get all the post data you need without those permission errors.

First, Why You’re Seeing That Error #

The "Field is empty or disallowed by the access token" message usually boils down to two things: missing specific permissions, or incorrect field formatting for reactions and insights when querying a list of posts.

Your single-post comment query works because comments has simpler permission requirements, but reactions and insights need more granular access and proper field syntax.

Step 1: Use a Valid Page Access Token (Not User Token) #

User Access Tokens can’t access Page insights or full reaction data—you must use a Page Access Token generated by a Page admin. Here’s how to ensure it has the right permissions:

• In Graph API Explorer, select your Page from the "Facebook Page" dropdown (or generate the token via the /me/accounts endpoint).
• Make sure the token includes these permissions:
  • pages_show_list (to access the Page itself)
  • pages_read_engagement (for reactions, comments, shares)
  • pages_read_insights (for post impressions, reach, and other metrics)
• Verify the token in the Access Token Debugger to confirm permissions are active and it’s not expired.

Step 2: Correct Field Syntax for Reactions and Insights #

You can’t just pass reactions or insights directly in a posts list query—you need to specify what data you want from them. Here’s the corrected API call:

{Page-ID}/posts?fields=message,shares,reactions.summary(total_count),insights.metric(post_impressions,post_reactions_total,post_comments,post_shares).period(lifetime)

Let’s break down the key parts:

• reactions.summary(total_count): Returns the total number of reactions across all types (LIKE, LOVE, WOW, etc.). If you want individual reaction counts, add specific types like reactions.type(LIKE).summary(total_count),reactions.type(LOVE).summary(total_count).
• insights.metric(...): Specifies exactly which metrics you need. The example includes:
  • post_impressions: Total exposure/views of the post
  • post_reactions_total: Aggregate reaction count (matches the reactions summary)
  • post_comments: Total comments on the post
  • post_shares: Total shares
• .period(lifetime): Fetches data for the post’s entire lifespan. You can switch to .period(day) or .period(week) if you want time-specific metrics.

Step 3: Troubleshooting Edge Cases #

• If insights still return empty: Some metrics require your Page to have a minimum number of followers (Facebook restricts certain data for small pages). Double-check the metric names—typos are common here!
• Expired tokens: Short-lived Page Tokens expire after 1 hour. Generate a long-lived token (valid for 60 days) using the /{User-ID}/accounts endpoint with your long-lived User Token.
• Admin access: Ensure you’re listed as a full admin of the Page—editors or moderators don’t have permission to access insights data.

Bonus: Getting Detailed Comment Data in the List Query #

If you want to include comment details (like you did in the single-post query) alongside other post data, add this to the fields parameter:

comments{message,like_count}

So the full call would look like:

{Page-ID}/posts?fields=message,shares,reactions.summary(total_count),insights.metric(post_impressions,post_reactions_total,post_comments,post_shares).period(lifetime),comments{message,like_count}

That should pull all the data you need to analyze user engagement: post content, shares, total reactions, impressions, comments, and comment likes.

内容的提问来源于stack exchange，提问作者Piotr Janczewski