Portal Community

add

Adds a reaction to a post via Graph API POST /{postId}/reactions.

FieldTypeRequiredDescription
postIdtext✓ YesTarget Facebook post ID.
reactionTypeselect✓ YesOne of LIKE, LOVE, HUH, HAHA, WOW, SAD, ANGRY (case-insensitive).

Example response:

{
  "postId": "123456789_987654321",
  "operationSuccess": true
}
Exact reaction set: FacebookInputValidator.ValidateReactionType only accepts the seven values above. Any other value — including newer UI-only reactions Facebook may display — is rejected client-side as FACEBOOK_VALIDATION_ERROR before a network call is made.
One reaction per caller: like Facebook's own UI, a single Page can only have one active reaction on a given post at a time. Calling add again with a different reactionType replaces the previous reaction rather than adding a second one.