diff --git a/CHANGELOG.md b/CHANGELOG.md
index 98428d4..c070416 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Fixed
+- Added missing user-agent headers
 
 ## [0.18.0] - 2022-11-17
 ### Changed
diff --git a/src/fetcher/activitypub.js b/src/fetcher/activitypub.js
index 655a0f0..c87a7c1 100644
--- a/src/fetcher/activitypub.js
+++ b/src/fetcher/activitypub.js
@@ -66,7 +66,8 @@ module.exports.fn = async (data, opts) => {
       const headers = {
         host,
         date: now.toUTCString(),
-        accept: 'application/activity+json'
+        accept: 'application/activity+json',
+        'User-Agent': `doipjs/${require('../../package.json').version}`
       }
 
       if (isConfigured && jsEnv.isNode) {
diff --git a/src/fetcher/matrix.js b/src/fetcher/matrix.js
index 97a0a26..9771c37 100644
--- a/src/fetcher/matrix.js
+++ b/src/fetcher/matrix.js
@@ -58,7 +58,10 @@ module.exports.fn = async (data, opts) => {
     const url = `https://${opts.claims.matrix.instance}/_matrix/client/r0/rooms/${data.roomId}/event/${data.eventId}?access_token=${opts.claims.matrix.accessToken}`
     axios.get(url,
       {
-        headers: { Accept: 'application/json' }
+        headers: {
+          Accept: 'application/json',
+          'User-Agent': `doipjs/${require('../../package.json').version}`
+        }
       })
       .then(res => {
         return res.data
diff --git a/src/fetcher/twitter.js b/src/fetcher/twitter.js
index 97880f7..6b39800 100644
--- a/src/fetcher/twitter.js
+++ b/src/fetcher/twitter.js
@@ -59,6 +59,7 @@ module.exports.fn = async (data, opts) => {
       {
         headers: {
           Accept: 'application/json',
+          'User-Agent': `doipjs/${require('../../package.json').version}`,
           Authorization: `Bearer ${opts.claims.twitter.bearerToken}`
         }
       }