diff --git a/Cargo.lock b/Cargo.lock
index 09108807c6..17b87db34d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1109,6 +1109,7 @@ dependencies = [
  "anyhow",
  "base64",
  "buzz-core",
+ "buzz-sdk",
  "buzz-ws-client",
  "chrono",
  "futures-util",
diff --git a/crates/buzz-relay/src/handlers/ingest.rs b/crates/buzz-relay/src/handlers/ingest.rs
index e41d2717fc..057ea972f7 100644
--- a/crates/buzz-relay/src/handlers/ingest.rs
+++ b/crates/buzz-relay/src/handlers/ingest.rs
@@ -676,7 +676,8 @@ pub(crate) fn effective_message_author(event: &Event, relay_pubkey: &nostr::Publ
     event.pubkey.to_bytes().to_vec()
 }
 
-/// Validate kind:40003 edit ownership — event.pubkey must match target's effective author.
+/// Validate kind:40003 edit ownership — event.pubkey must match target's effective author,
+/// or the actor must be the owning human of the agent that authored the target message.
 async fn validate_edit_ownership(
     community_id: CommunityId,
     event: &Event,
@@ -723,8 +724,36 @@ async fn validate_edit_ownership(
 
     let author = effective_message_author(&target_event.event, &state.relay_keypair.public_key());
     let actor = event.pubkey.to_bytes().to_vec();
-    if author != actor {
-        return Err("must be event author to edit".to_string());
+    if author == actor {
+        // Author editing their own message: re-gate on membership/open visibility so that
+        // a removed private-channel member cannot mutate old messages after access is revoked.
+        if let Some(ch_id) = target_event.channel_id {
+            let is_member = state
+                .is_member_cached(community_id, ch_id, &actor)
+                .await
+                .map_err(|e| format!("db error checking membership: {e}"))?;
+            if !is_member {
+                let is_open = state
+                    .db
+                    .get_channel(community_id, ch_id)
+                    .await
+                    .map(|ch| ch.visibility == "open")
+                    .unwrap_or(false);
+                if !is_open {
+                    return Err("restricted: not a channel member".to_string());
+                }
+            }
+        }
+    } else {
+        // Allow the owning human to edit messages authored by their agent.
+        let is_owner = state
+            .db
+            .is_agent_owner(community_id, &author, &actor)
+            .await
+            .map_err(|e| format!("db error checking agent ownership: {e}"))?;
+        if !is_owner {
+            return Err("must be event author to edit".to_string());
+        }
     }
     Ok(())
 }
@@ -1379,8 +1408,17 @@ async fn ingest_event_inner(
     if let Some(ch_id) = channel_id {
         // kind:9021 (join) doesn't require prior membership.
         // kind:9007 (create) — channel doesn't exist yet; creator becomes owner in step 16.
-        let skip_membership =
-            kind_u32 == KIND_NIP29_JOIN_REQUEST || kind_u32 == KIND_NIP29_CREATE_GROUP;
+        // kind:40003/9002/9005/9008 — per-kind validators are the authority; they
+        // individually enforce authorization and fail closed. Bypassing the generic
+        // member/open gate here lets the owning human act on private agent channels
+        // without being a member (OQ1 decision; see validate_edit_ownership /
+        // validate_admin_event for per-kind enforcement).
+        let skip_membership = kind_u32 == KIND_NIP29_JOIN_REQUEST
+            || kind_u32 == KIND_NIP29_CREATE_GROUP
+            || kind_u32 == KIND_STREAM_MESSAGE_EDIT
+            || kind_u32 == KIND_NIP29_EDIT_METADATA
+            || kind_u32 == KIND_NIP29_DELETE_EVENT
+            || kind_u32 == KIND_NIP29_DELETE_GROUP;
         if !skip_membership {
             // Spec AuthCheck (line 794): emit the verdict at the actual
             // call site. claimed_community comes from the event's h tag
diff --git a/crates/buzz-relay/src/handlers/side_effects.rs b/crates/buzz-relay/src/handlers/side_effects.rs
index f5c5d36931..ae3beefe97 100644
--- a/crates/buzz-relay/src/handlers/side_effects.rs
+++ b/crates/buzz-relay/src/handlers/side_effects.rs
@@ -216,6 +216,30 @@ pub async fn validate_standard_deletion_event(
     Ok(())
 }
 
+/// Returns `true` if `actor_bytes` is the NIP-OA owner of **any** active owner-role
+/// member in `members`. Used by kind:9002 and kind:9008 to authorize the owning
+/// human of a channel's agent-owner(s) even when the human is not a channel member.
+///
+/// Checking all active owners (not just the first) is correct under co-ownership:
+/// an agent may be promoted to owner later, or multiple agents may co-own a channel.
+async fn actor_owns_any_owner_agent(
+    state: &Arc<AppState>,
+    community_id: buzz_core::CommunityId,
+    members: &[buzz_db::channel::MemberRecord],
+    actor_bytes: &[u8],
+) -> anyhow::Result<bool> {
+    for owner in members.iter().filter(|m| m.role == "owner") {
+        if state
+            .db
+            .is_agent_owner(community_id, &owner.pubkey, actor_bytes)
+            .await?
+        {
+            return Ok(true);
+        }
+    }
+    Ok(false)
+}
+
 /// Validate an admin kind event BEFORE storage.
 pub async fn validate_admin_event(
     tenant: &TenantContext,
@@ -459,9 +483,24 @@ pub async fn validate_admin_event(
                 let actor_member = members.iter().find(|m| m.pubkey == actor_bytes);
                 match actor_member {
                     Some(m) if m.role == "owner" || m.role == "admin" => Ok(()),
-                    _ => Err(anyhow::anyhow!(
-                        "actor not authorized for name/about/archived/visibility/ttl changes"
-                    )),
+                    _ => {
+                        // Allow the owning human of any active owner-role agent in the
+                        // channel, even when the human is not a channel member —
+                        // diverges from kind:9001 intentionally.
+                        if actor_owns_any_owner_agent(
+                            state,
+                            tenant.community(),
+                            &members,
+                            &actor_bytes,
+                        )
+                        .await?
+                        {
+                            return Ok(());
+                        }
+                        Err(anyhow::anyhow!(
+                            "actor not authorized for name/about/archived/visibility/ttl changes"
+                        ))
+                    }
                 }
             } else {
                 // topic/purpose: any member
@@ -516,26 +555,66 @@ pub async fn validate_admin_event(
             let author =
                 effective_message_author(&target_event.event, &state.relay_keypair.public_key());
             if author == actor_bytes {
-                return Ok(()); // Author can always delete their own messages
+                // Author deleting their own message: re-gate on membership/open visibility so that
+                // a removed private-channel member cannot mutate old messages after access is revoked.
+                let is_member = state
+                    .is_member_cached(tenant.community(), channel_id, &actor_bytes)
+                    .await?;
+                if is_member {
+                    return Ok(());
+                }
+                let is_open = state
+                    .db
+                    .get_channel(tenant.community(), channel_id)
+                    .await
+                    .map(|ch| ch.visibility == "open")
+                    .unwrap_or(false);
+                if is_open {
+                    return Ok(());
+                }
+                // Not a member and channel is private — fall through to owner/admin/owner-of-agent check.
             }
 
-            // Not the author — must be owner/admin.
+            // Not the author, or author who is no longer a member of a private channel —
+            // must be owner/admin or the owning human of the message's agent-author.
             let members = state.db.get_members(tenant.community(), channel_id).await?;
             let actor_member = members.iter().find(|m| m.pubkey == actor_bytes);
             match actor_member {
                 Some(m) if m.role == "owner" || m.role == "admin" => Ok(()),
-                _ => Err(anyhow::anyhow!(
-                    "must be event author or channel owner/admin"
-                )),
+                _ => {
+                    // Allow the owning human of the agent that authored the target message,
+                    // even when the human is not a channel member.
+                    if state
+                        .db
+                        .is_agent_owner(tenant.community(), &author, &actor_bytes)
+                        .await?
+                    {
+                        Ok(())
+                    } else {
+                        Err(anyhow::anyhow!(
+                            "must be event author or channel owner/admin"
+                        ))
+                    }
+                }
             }
         }
         9008 => {
-            // DELETE_GROUP: owner only
+            // DELETE_GROUP: owner only, or the owning human of the channel's agent-owner.
             let members = state.db.get_members(tenant.community(), channel_id).await?;
             let actor_member = members.iter().find(|m| m.pubkey == actor_bytes);
             match actor_member {
                 Some(m) if m.role == "owner" => Ok(()),
-                _ => Err(anyhow::anyhow!("only owner can delete group")),
+                _ => {
+                    // Allow the owning human of any active owner-role agent in the
+                    // channel, even when the human is not a channel member —
+                    // diverges from kind:9001 intentionally.
+                    if actor_owns_any_owner_agent(state, tenant.community(), &members, &actor_bytes)
+                        .await?
+                    {
+                        return Ok(());
+                    }
+                    Err(anyhow::anyhow!("only owner can delete group"))
+                }
             }
         }
         9022 => {
diff --git a/crates/buzz-test-client/Cargo.toml b/crates/buzz-test-client/Cargo.toml
index bba41127b3..7ce3e2bc31 100644
--- a/crates/buzz-test-client/Cargo.toml
+++ b/crates/buzz-test-client/Cargo.toml
@@ -35,6 +35,7 @@ rand = { workspace = true }
 sha2 = { workspace = true }
 chrono = { workspace = true }
 s3 = { version = "0.37", package = "rust-s3", default-features = false, features = ["tokio-rustls-tls", "fail-on-err", "tags"] }
+buzz-sdk = { workspace = true }
 
 [[bin]]
 name = "buzz-test-cli"
diff --git a/crates/buzz-test-client/src/lib.rs b/crates/buzz-test-client/src/lib.rs
index 8cf3ec790f..89bff3020d 100644
--- a/crates/buzz-test-client/src/lib.rs
+++ b/crates/buzz-test-client/src/lib.rs
@@ -106,6 +106,18 @@ impl BuzzTestClient {
         Ok(())
     }
 
+    /// Performs NIP-42 authentication with a NIP-OA `auth` tag, establishing
+    /// the agent→owner relationship in the relay's DB.  Call this as the
+    /// *agent* connection; the tag must be signed by `owner_keys`.
+    pub async fn authenticate_with_nip_oa(
+        &mut self,
+        agent_keys: &Keys,
+        auth_tag: &Tag,
+    ) -> Result<(), TestClientError> {
+        self.inner.authenticate(agent_keys, Some(auth_tag)).await?;
+        Ok(())
+    }
+
     /// Sends a signed event to the relay and waits for the OK response.
     pub async fn send_event(&mut self, event: Event) -> Result<OkResponse, TestClientError> {
         Ok(self.inner.send_event(event).await?)
diff --git a/crates/buzz-test-client/tests/e2e_human_edit_agent_content.rs b/crates/buzz-test-client/tests/e2e_human_edit_agent_content.rs
new file mode 100644
index 0000000000..57a888e102
--- /dev/null
+++ b/crates/buzz-test-client/tests/e2e_human_edit_agent_content.rs
@@ -0,0 +1,899 @@
+//! End-to-end tests for human owners editing/managing content authored by
+//! their agents — all four authorization predicate sites:
+//!
+//! - kind:40003 message edit (`validate_edit_ownership`)
+//! - kind:9005 DELETE_EVENT (`validate_admin_event` 9005 branch)
+//! - kind:9002 EDIT_METADATA privileged-tag branch
+//! - kind:9008 DELETE_GROUP
+//!
+//! The owner→agent relationship is established via NIP-OA: the agent
+//! connects and authenticates with an `auth` tag signed by the owner.
+//!
+//! # Running
+//!
+//! Start the relay, then run:
+//!
+//! ```text
+//! cargo test --test e2e_human_edit_agent_content -- --ignored
+//! ```
+
+use buzz_sdk::nip_oa;
+use buzz_test_client::BuzzTestClient;
+use nostr::{EventBuilder, Keys, Kind, Tag};
+
+fn relay_url() -> String {
+    std::env::var("RELAY_URL").unwrap_or_else(|_| "ws://localhost:3000".to_string())
+}
+
+fn relay_http_url() -> String {
+    relay_url()
+        .replace("wss://", "https://")
+        .replace("ws://", "http://")
+        .trim_end_matches('/')
+        .to_string()
+}
+
+/// Create a fresh channel owned by `owner_keys`, return the channel UUID string.
+async fn create_agent_owned_channel(agent_keys: &Keys) -> String {
+    let http = reqwest::Client::new();
+    let channel_uuid = uuid::Uuid::new_v4();
+
+    let event = EventBuilder::new(Kind::Custom(9007), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_uuid.to_string()]).unwrap(),
+            Tag::parse(["name", &format!("haec-test-{}", channel_uuid.simple())]).unwrap(),
+            Tag::parse(["channel_type", "stream"]).unwrap(),
+            Tag::parse(["visibility", "open"]).unwrap(),
+        ])
+        .sign_with_keys(agent_keys)
+        .unwrap();
+
+    let resp = http
+        .post(format!("{}/events", relay_http_url()))
+        .header("X-Pubkey", &agent_keys.public_key().to_hex())
+        .header("Content-Type", "application/json")
+        .body(serde_json::to_string(&event).unwrap())
+        .send()
+        .await
+        .expect("submit create-channel event");
+    assert!(
+        resp.status().is_success(),
+        "channel creation failed: {}",
+        resp.status()
+    );
+    let body: serde_json::Value = resp.json().await.unwrap();
+    assert!(
+        body["accepted"].as_bool().unwrap_or(false),
+        "channel creation not accepted: {body}"
+    );
+    channel_uuid.to_string()
+}
+
+/// Build a NIP-OA auth tag for `agent_keys` signed by `owner_keys`.
+fn make_nip_oa_auth_tag(owner_keys: &Keys, agent_keys: &Keys) -> Tag {
+    let tag_json = nip_oa::compute_auth_tag(owner_keys, &agent_keys.public_key(), "kind=9")
+        .expect("compute_auth_tag");
+    nip_oa::parse_auth_tag(&tag_json).expect("parse_auth_tag")
+}
+
+/// Connect `agent_keys` to the relay with NIP-OA, establishing owner→agent in the DB.
+/// Returns the connected (authenticated) client for the agent.
+async fn connect_agent_with_owner(agent_keys: &Keys, owner_keys: &Keys) -> BuzzTestClient {
+    let url = relay_url();
+    let auth_tag = make_nip_oa_auth_tag(owner_keys, agent_keys);
+    let mut client = BuzzTestClient::connect_unauthenticated(&url)
+        .await
+        .expect("connect agent unauthenticated");
+    client
+        .authenticate_with_nip_oa(agent_keys, &auth_tag)
+        .await
+        .expect("NIP-OA auth");
+    client
+}
+
+// ─── kind:40003 message edit ───────────────────────────────────────────────
+
+/// Owner can edit a message authored by their agent via kind:40003.
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_edit_agent_message() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership in DB.
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    // Agent sends a message.
+    let content = format!("agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message");
+    assert!(ok.accepted, "agent message rejected: {}", ok.message);
+    let msg_event_id = ok.event_id;
+
+    // Owner sends a kind:40003 edit event targeting the agent's message.
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+
+    let edit_event = EventBuilder::new(Kind::Custom(40003), "corrected content")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+
+    let ok = owner_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit");
+    assert!(
+        ok.accepted,
+        "owner edit of agent message rejected: {}",
+        ok.message
+    );
+
+    agent_client.disconnect().await.ok();
+    owner_client.disconnect().await.ok();
+}
+
+/// An unrelated third party cannot edit an agent's message.
+#[tokio::test]
+#[ignore]
+async fn test_third_party_cannot_edit_agent_message() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let third_party_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    let content = format!("agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message");
+    assert!(ok.accepted, "agent message rejected: {}", ok.message);
+    let msg_event_id = ok.event_id;
+
+    let mut third_party_client = BuzzTestClient::connect(&relay_url(), &third_party_keys)
+        .await
+        .expect("connect third party");
+
+    let edit_event = EventBuilder::new(Kind::Custom(40003), "malicious edit")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&third_party_keys)
+        .unwrap();
+
+    let ok = third_party_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit attempt");
+    assert!(
+        !ok.accepted,
+        "third party should NOT be able to edit agent message, but was accepted"
+    );
+
+    agent_client.disconnect().await.ok();
+    third_party_client.disconnect().await.ok();
+}
+
+/// The agent itself can still edit its own message (self-edit unchanged).
+#[tokio::test]
+#[ignore]
+async fn test_agent_can_self_edit_message() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    let content = format!("agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message");
+    assert!(ok.accepted, "agent message rejected: {}", ok.message);
+    let msg_event_id = ok.event_id;
+
+    let edit_event = EventBuilder::new(Kind::Custom(40003), "agent self-edit")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+
+    let ok = agent_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit");
+    assert!(ok.accepted, "agent self-edit rejected: {}", ok.message);
+
+    agent_client.disconnect().await.ok();
+}
+
+// ─── kind:9005 DELETE_EVENT ─────────────────────────────────────────────────
+
+/// Owner can delete a message authored by their agent via kind:9005.
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_delete_agent_message() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    let content = format!("agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message");
+    assert!(ok.accepted, "agent message rejected: {}", ok.message);
+    let msg_event_id = ok.event_id;
+
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+
+    let delete_event = EventBuilder::new(Kind::Custom(9005), "")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+
+    let ok = owner_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete");
+    assert!(
+        ok.accepted,
+        "owner delete of agent message rejected: {}",
+        ok.message
+    );
+
+    agent_client.disconnect().await.ok();
+    owner_client.disconnect().await.ok();
+}
+
+/// An unrelated third party cannot delete an agent's message.
+#[tokio::test]
+#[ignore]
+async fn test_third_party_cannot_delete_agent_message() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let third_party_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    let content = format!("agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message");
+    assert!(ok.accepted, "agent message rejected: {}", ok.message);
+    let msg_event_id = ok.event_id;
+
+    let mut third_party_client = BuzzTestClient::connect(&relay_url(), &third_party_keys)
+        .await
+        .expect("connect third party");
+
+    let delete_event = EventBuilder::new(Kind::Custom(9005), "")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&third_party_keys)
+        .unwrap();
+
+    let ok = third_party_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete attempt");
+    assert!(
+        !ok.accepted,
+        "third party should NOT be able to delete agent message, but was accepted"
+    );
+
+    agent_client.disconnect().await.ok();
+    third_party_client.disconnect().await.ok();
+}
+
+// ─── kind:9002 EDIT_METADATA ────────────────────────────────────────────────
+
+/// Owner can edit metadata (name/archived) of a channel owned by their agent,
+/// even when the owner is not a channel member.
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_edit_agent_channel_metadata() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+
+    // Agent creates the channel (agent is the channel owner-member).
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership.
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    // Owner sends kind:9002 to rename the channel — owner is NOT a member.
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+
+    let edit_event = EventBuilder::new(Kind::Custom(9002), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["name", "owner-renamed-channel"]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+
+    let ok = owner_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit metadata");
+    assert!(
+        ok.accepted,
+        "owner edit of agent channel metadata rejected: {}",
+        ok.message
+    );
+
+    owner_client.disconnect().await.ok();
+}
+
+/// Owner can archive an agent's channel via kind:9002.
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_archive_agent_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+
+    let archive_event = EventBuilder::new(Kind::Custom(9002), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["archived", "true"]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+
+    let ok = owner_client
+        .send_event(archive_event)
+        .await
+        .expect("send archive");
+    assert!(
+        ok.accepted,
+        "owner archive of agent channel rejected: {}",
+        ok.message
+    );
+
+    owner_client.disconnect().await.ok();
+}
+
+/// Unrelated third party cannot edit metadata of an agent's channel.
+#[tokio::test]
+#[ignore]
+async fn test_third_party_cannot_edit_agent_channel_metadata() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let third_party_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    let mut third_party_client = BuzzTestClient::connect(&relay_url(), &third_party_keys)
+        .await
+        .expect("connect third party");
+
+    let edit_event = EventBuilder::new(Kind::Custom(9002), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["name", "hijacked-name"]).unwrap(),
+        ])
+        .sign_with_keys(&third_party_keys)
+        .unwrap();
+
+    let ok = third_party_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit attempt");
+    assert!(
+        !ok.accepted,
+        "third party should NOT be able to edit agent channel metadata, but was accepted"
+    );
+
+    third_party_client.disconnect().await.ok();
+}
+
+// ─── kind:9008 DELETE_GROUP ─────────────────────────────────────────────────
+
+/// Owner can delete a channel owned by their agent via kind:9008,
+/// even when the owner is not a channel member.
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_delete_agent_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership.
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    // Owner sends kind:9008 to delete the channel — owner is NOT a member.
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+
+    let delete_event = EventBuilder::new(Kind::Custom(9008), "")
+        .tags(vec![Tag::parse(["h", &channel_id]).unwrap()])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+
+    let ok = owner_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete group");
+    assert!(
+        ok.accepted,
+        "owner delete of agent channel rejected: {}",
+        ok.message
+    );
+
+    owner_client.disconnect().await.ok();
+}
+
+/// Unrelated third party cannot delete an agent's channel.
+#[tokio::test]
+#[ignore]
+async fn test_third_party_cannot_delete_agent_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let third_party_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    let mut third_party_client = BuzzTestClient::connect(&relay_url(), &third_party_keys)
+        .await
+        .expect("connect third party");
+
+    let delete_event = EventBuilder::new(Kind::Custom(9008), "")
+        .tags(vec![Tag::parse(["h", &channel_id]).unwrap()])
+        .sign_with_keys(&third_party_keys)
+        .unwrap();
+
+    let ok = third_party_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete attempt");
+    assert!(
+        !ok.accepted,
+        "third party should NOT be able to delete agent channel, but was accepted"
+    );
+
+    third_party_client.disconnect().await.ok();
+}
+
+/// Create a fresh **private** channel owned by `agent_keys`, return the channel UUID string.
+async fn create_private_agent_owned_channel(agent_keys: &Keys) -> String {
+    let http = reqwest::Client::new();
+    let channel_uuid = uuid::Uuid::new_v4();
+
+    let event = EventBuilder::new(Kind::Custom(9007), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_uuid.to_string()]).unwrap(),
+            Tag::parse([
+                "name",
+                &format!("haec-private-test-{}", channel_uuid.simple()),
+            ])
+            .unwrap(),
+            Tag::parse(["channel_type", "stream"]).unwrap(),
+            Tag::parse(["visibility", "private"]).unwrap(),
+        ])
+        .sign_with_keys(agent_keys)
+        .unwrap();
+
+    let resp = http
+        .post(format!("{}/events", relay_http_url()))
+        .header("X-Pubkey", &agent_keys.public_key().to_hex())
+        .header("Content-Type", "application/json")
+        .body(serde_json::to_string(&event).unwrap())
+        .send()
+        .await
+        .expect("submit create-private-channel event");
+    assert!(
+        resp.status().is_success(),
+        "private channel creation failed: {}",
+        resp.status()
+    );
+    let body: serde_json::Value = resp.json().await.unwrap();
+    assert!(
+        body["accepted"].as_bool().unwrap_or(false),
+        "private channel creation not accepted: {body}"
+    );
+    channel_uuid.to_string()
+}
+
+// ─── Private-channel coverage (Fix 1 regression guard) ──────────────────────
+//
+// These tests verify that the membership-gate bypass works on private channels —
+// i.e., a non-member owning human can act on private agent-owned content.
+// Previously all four predicates were unreachable for private channels because
+// check_channel_membership rejected non-members before the per-kind validators ran.
+
+/// Owner can edit a message in a private agent-owned channel (non-member owner allowed).
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_edit_agent_message_in_private_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership; agent sends a message.
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    let content = format!("private-agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message to private channel");
+    assert!(
+        ok.accepted,
+        "agent message to private channel rejected: {}",
+        ok.message
+    );
+    let msg_event_id = ok.event_id;
+    agent_client.disconnect().await.ok();
+
+    // Owner (not a channel member) edits the agent's message.
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+    let edit_event = EventBuilder::new(Kind::Custom(40003), "edited content")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+    let ok = owner_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit");
+    assert!(
+        ok.accepted,
+        "owner edit of agent message in private channel rejected (membership gate not bypassed): {}",
+        ok.message
+    );
+    owner_client.disconnect().await.ok();
+}
+
+/// Owner can delete a message in a private agent-owned channel (non-member owner allowed).
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_delete_agent_message_in_private_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    let content = format!("private-agent-msg-{}", uuid::Uuid::new_v4());
+    let ok = agent_client
+        .send_text_message(&agent_keys, &channel_id, &content, 9)
+        .await
+        .expect("agent send message to private channel");
+    assert!(
+        ok.accepted,
+        "agent message to private channel rejected: {}",
+        ok.message
+    );
+    let msg_event_id = ok.event_id;
+    agent_client.disconnect().await.ok();
+
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+    let delete_event = EventBuilder::new(Kind::Custom(9005), "")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+    let ok = owner_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete");
+    assert!(
+        ok.accepted,
+        "owner delete of agent message in private channel rejected (membership gate not bypassed): {}",
+        ok.message
+    );
+    owner_client.disconnect().await.ok();
+}
+
+/// Owner can edit metadata of a private agent-owned channel (non-member owner allowed).
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_edit_metadata_of_private_agent_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+    let edit_event = EventBuilder::new(Kind::Custom(9002), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["name", "owner-renamed-private-channel"]).unwrap(),
+        ])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+    let ok = owner_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit metadata");
+    assert!(
+        ok.accepted,
+        "owner edit of private agent channel metadata rejected (membership gate not bypassed): {}",
+        ok.message
+    );
+    owner_client.disconnect().await.ok();
+}
+
+/// Owner can delete a private agent-owned channel (non-member owner allowed).
+#[tokio::test]
+#[ignore]
+async fn test_owner_can_delete_private_agent_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    let agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+    agent_client.disconnect().await.ok();
+
+    let mut owner_client = BuzzTestClient::connect(&relay_url(), &owner_keys)
+        .await
+        .expect("connect owner");
+    let delete_event = EventBuilder::new(Kind::Custom(9008), "")
+        .tags(vec![Tag::parse(["h", &channel_id]).unwrap()])
+        .sign_with_keys(&owner_keys)
+        .unwrap();
+    let ok = owner_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete group");
+    assert!(
+        ok.accepted,
+        "owner delete of private agent channel rejected (membership gate not bypassed): {}",
+        ok.message
+    );
+    owner_client.disconnect().await.ok();
+}
+
+/// Agent itself can still delete its own channel (self-delete unchanged).
+#[tokio::test]
+#[ignore]
+async fn test_agent_can_self_delete_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let channel_id = create_agent_owned_channel(&agent_keys).await;
+
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    let delete_event = EventBuilder::new(Kind::Custom(9008), "")
+        .tags(vec![Tag::parse(["h", &channel_id]).unwrap()])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+
+    let ok = agent_client
+        .send_event(delete_event)
+        .await
+        .expect("send self-delete group");
+    assert!(
+        ok.accepted,
+        "agent self-delete of own channel rejected: {}",
+        ok.message
+    );
+
+    agent_client.disconnect().await.ok();
+}
+
+// ─── Removed-author rejection tests (Option A regression guard) ─────────────
+//
+// These tests verify that removing a user from a private channel revokes their
+// ability to edit or delete their own historical messages.  Before Option A,
+// adding 40003/9005 to skip_membership also widened the self-author fast-path,
+// allowing removed users to mutate private-channel history.
+
+/// A user removed from a private channel CANNOT edit their own old messages.
+#[tokio::test]
+#[ignore]
+async fn test_removed_author_cannot_edit_own_message_in_private_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let victim_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership; agent is now in the channel.
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    // Agent adds victim to the private channel via kind:9000 (PUT_USER).
+    let add_event = EventBuilder::new(Kind::Custom(9000), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["p", &victim_keys.public_key().to_hex()]).unwrap(),
+        ])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+    let ok = agent_client
+        .send_event(add_event)
+        .await
+        .expect("send PUT_USER");
+    assert!(
+        ok.accepted,
+        "agent failed to add victim to private channel: {}",
+        ok.message
+    );
+
+    // Victim connects and sends a message while still a member.
+    let mut victim_client = BuzzTestClient::connect(&relay_url(), &victim_keys)
+        .await
+        .expect("connect victim");
+    let content = format!("victim-msg-{}", uuid::Uuid::new_v4());
+    let ok = victim_client
+        .send_text_message(&victim_keys, &channel_id, &content, 9)
+        .await
+        .expect("victim send message");
+    assert!(
+        ok.accepted,
+        "victim message rejected while still a member: {}",
+        ok.message
+    );
+    let msg_event_id = ok.event_id;
+
+    // Agent removes victim from the channel via kind:9001 (REMOVE_USER).
+    let remove_event = EventBuilder::new(Kind::Custom(9001), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["p", &victim_keys.public_key().to_hex()]).unwrap(),
+        ])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+    let ok = agent_client
+        .send_event(remove_event)
+        .await
+        .expect("send REMOVE_USER");
+    assert!(
+        ok.accepted,
+        "agent failed to remove victim from private channel: {}",
+        ok.message
+    );
+    agent_client.disconnect().await.ok();
+
+    // Victim (now removed) attempts to edit their old message — must be rejected.
+    let edit_event = EventBuilder::new(Kind::Custom(40003), "edited content after removal")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&victim_keys)
+        .unwrap();
+    let ok = victim_client
+        .send_event(edit_event)
+        .await
+        .expect("send edit attempt");
+    assert!(
+        !ok.accepted,
+        "removed author should NOT be able to edit old message in private channel, but was accepted"
+    );
+    victim_client.disconnect().await.ok();
+}
+
+/// A user removed from a private channel CANNOT delete their own old messages.
+#[tokio::test]
+#[ignore]
+async fn test_removed_author_cannot_delete_own_message_in_private_channel() {
+    let owner_keys = Keys::generate();
+    let agent_keys = Keys::generate();
+    let victim_keys = Keys::generate();
+    let channel_id = create_private_agent_owned_channel(&agent_keys).await;
+
+    // Establish NIP-OA ownership; agent is now in the channel.
+    let mut agent_client = connect_agent_with_owner(&agent_keys, &owner_keys).await;
+
+    // Agent adds victim to the private channel via kind:9000 (PUT_USER).
+    let add_event = EventBuilder::new(Kind::Custom(9000), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["p", &victim_keys.public_key().to_hex()]).unwrap(),
+        ])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+    let ok = agent_client
+        .send_event(add_event)
+        .await
+        .expect("send PUT_USER");
+    assert!(
+        ok.accepted,
+        "agent failed to add victim to private channel: {}",
+        ok.message
+    );
+
+    // Victim connects and sends a message while still a member.
+    let mut victim_client = BuzzTestClient::connect(&relay_url(), &victim_keys)
+        .await
+        .expect("connect victim");
+    let content = format!("victim-msg-{}", uuid::Uuid::new_v4());
+    let ok = victim_client
+        .send_text_message(&victim_keys, &channel_id, &content, 9)
+        .await
+        .expect("victim send message");
+    assert!(
+        ok.accepted,
+        "victim message rejected while still a member: {}",
+        ok.message
+    );
+    let msg_event_id = ok.event_id;
+
+    // Agent removes victim from the channel via kind:9001 (REMOVE_USER).
+    let remove_event = EventBuilder::new(Kind::Custom(9001), "")
+        .tags(vec![
+            Tag::parse(["h", &channel_id]).unwrap(),
+            Tag::parse(["p", &victim_keys.public_key().to_hex()]).unwrap(),
+        ])
+        .sign_with_keys(&agent_keys)
+        .unwrap();
+    let ok = agent_client
+        .send_event(remove_event)
+        .await
+        .expect("send REMOVE_USER");
+    assert!(
+        ok.accepted,
+        "agent failed to remove victim from private channel: {}",
+        ok.message
+    );
+    agent_client.disconnect().await.ok();
+
+    // Victim (now removed) attempts to delete their old message — must be rejected.
+    let delete_event = EventBuilder::new(Kind::Custom(9005), "")
+        .tags(vec![
+            Tag::parse(["e", &msg_event_id]).unwrap(),
+            Tag::parse(["h", &channel_id]).unwrap(),
+        ])
+        .sign_with_keys(&victim_keys)
+        .unwrap();
+    let ok = victim_client
+        .send_event(delete_event)
+        .await
+        .expect("send delete attempt");
+    assert!(
+        !ok.accepted,
+        "removed author should NOT be able to delete old message in private channel, but was accepted"
+    );
+    victim_client.disconnect().await.ok();
+}
diff --git a/desktop/playwright.config.ts b/desktop/playwright.config.ts
index 0c827cc95f..fecfc7103c 100644
--- a/desktop/playwright.config.ts
+++ b/desktop/playwright.config.ts
@@ -58,6 +58,7 @@ export default defineConfig({
         "**/overscroll-boundary.spec.ts",
         "**/cold-switch-longtask.perf.ts",
         "**/timeline-no-shift.spec.ts",
+        "**/human-edit-agent-content.spec.ts",
       ],
       use: {
         ...devices["Desktop Chrome"],
diff --git a/desktop/src/features/channels/ui/ChannelManagementModerationActions.tsx b/desktop/src/features/channels/ui/ChannelManagementModerationActions.tsx
index 7a14546ada..c5e192fd2a 100644
--- a/desktop/src/features/channels/ui/ChannelManagementModerationActions.tsx
+++ b/desktop/src/features/channels/ui/ChannelManagementModerationActions.tsx
@@ -29,7 +29,7 @@ type ChannelManagementModerationActionsProps = {
   isArchived: boolean;
   isDark: boolean;
   isDeleteDialogOpen: boolean;
-  isOwner: boolean;
+  canDeleteChannel: boolean;
   resolvedChannelName: string;
   unarchiveChannelMutation: ChannelMutation;
 };
@@ -43,7 +43,7 @@ export function ChannelManagementModerationActions({
   isArchived,
   isDark,
   isDeleteDialogOpen,
-  isOwner,
+  canDeleteChannel,
   resolvedChannelName,
   unarchiveChannelMutation,
 }: ChannelManagementModerationActionsProps) {
@@ -104,7 +104,7 @@ export function ChannelManagementModerationActions({
           <Archive className="h-4 w-4" />
         </Button>
       )}
-      {isOwner ? (
+      {canDeleteChannel ? (
         <AlertDialog
           onOpenChange={handleDeleteDialogOpenChange}
           open={isDeleteDialogOpen}
diff --git a/desktop/src/features/channels/ui/ChannelManagementSheet.tsx b/desktop/src/features/channels/ui/ChannelManagementSheet.tsx
index eab5f80a6b..ffdad6f30c 100644
--- a/desktop/src/features/channels/ui/ChannelManagementSheet.tsx
+++ b/desktop/src/features/channels/ui/ChannelManagementSheet.tsx
@@ -37,8 +37,11 @@ import {
   formatTtlDuration,
   parseTtlDuration,
 } from "@/features/channels/lib/ephemeralChannel";
+import { ownsAuthorAgent } from "@/features/profile/lib/identity";
+import { useUsersBatchQuery } from "@/features/profile/hooks";
 import type { Channel } from "@/shared/api/types";
 import { cn } from "@/shared/lib/cn";
+import { normalizePubkey } from "@/shared/lib/pubkey";
 import { useTheme } from "@/shared/theme/ThemeProvider";
 import { Button } from "@/shared/ui/button";
 import {
@@ -133,9 +136,38 @@ export function ChannelManagementSheet({
   const selfMember =
     members.find((member) => member.pubkey === currentPubkey) ?? null;
   const hasResolvedMembership = membersQuery.data !== undefined;
-  const isOwner = selfMember?.role === "owner";
+
+  // Collect owner-role member pubkeys to look up their NIP-OA ownerPubkey.
+  // This is what surfaces the "you own the agent that owns this channel" path.
+  const ownerMemberPubkeys = React.useMemo(
+    () =>
+      members
+        .filter((m) => m.role === "owner" && m.pubkey !== currentPubkey)
+        .map((m) => m.pubkey),
+    [members, currentPubkey],
+  );
+  const ownerProfilesQuery = useUsersBatchQuery(ownerMemberPubkeys, {
+    enabled: open && ownerMemberPubkeys.length > 0,
+  });
+  // True when an owner-role member of this channel is an agent owned by the
+  // current user — mirrors the relay's is_agent_owner gate.
+  const canManageOwnedAgentChannel = React.useMemo(() => {
+    if (!currentPubkey || !ownerProfilesQuery.data) return false;
+    return ownerMemberPubkeys.some((pubkey) =>
+      ownsAuthorAgent(
+        ownerProfilesQuery.data?.profiles[normalizePubkey(pubkey)],
+        currentPubkey,
+      ),
+    );
+  }, [currentPubkey, ownerMemberPubkeys, ownerProfilesQuery.data]);
+
+  const isSelfOwner = selfMember?.role === "owner";
+  // Capability: may delete this channel (self-owner OR owns the agent-owner).
+  const canDeleteChannel = isSelfOwner || canManageOwnedAgentChannel;
   const canManageChannel =
-    selfMember?.role === "owner" || selfMember?.role === "admin";
+    selfMember?.role === "owner" ||
+    selfMember?.role === "admin" ||
+    canManageOwnedAgentChannel;
   const canEditNarrative =
     canManageChannel && selfMember !== null && detail?.channelType !== "dm";
   const isArchived =
@@ -353,7 +385,7 @@ export function ChannelManagementSheet({
             isArchived={isArchived}
             isDark={isDark}
             isDeleteDialogOpen={isDeleteDialogOpen}
-            isOwner={isOwner}
+            canDeleteChannel={canDeleteChannel}
             mode={auxiliaryPanelMode}
             transparentChrome={transparentChrome}
             joinChannelMutation={joinChannelMutation}
@@ -399,7 +431,7 @@ export function ChannelManagementSheet({
               isArchived={isArchived}
               isDark={isDark}
               isDeleteDialogOpen={isDeleteDialogOpen}
-              isOwner={isOwner}
+              canDeleteChannel={canDeleteChannel}
               mode={auxiliaryPanelMode}
               transparentChrome={transparentChrome}
               joinChannelMutation={joinChannelMutation}
@@ -635,7 +667,7 @@ type ChannelManagementPanelContentProps = {
   isArchived: boolean;
   isDark: boolean;
   isDeleteDialogOpen: boolean;
-  isOwner: boolean;
+  canDeleteChannel: boolean; // true when caller may delete the channel
   mode: AuxiliaryPanelMode;
   transparentChrome?: boolean;
   joinChannelMutation: ChannelMutation;
@@ -667,7 +699,7 @@ function ChannelManagementPanelContent({
   isArchived,
   isDark,
   isDeleteDialogOpen,
-  isOwner,
+  canDeleteChannel,
   mode,
   transparentChrome = false,
   joinChannelMutation,
@@ -933,7 +965,7 @@ function ChannelManagementPanelContent({
           isArchived={isArchived}
           isDark={isDark}
           isDeleteDialogOpen={isDeleteDialogOpen}
-          isOwner={isOwner}
+          canDeleteChannel={canDeleteChannel}
           resolvedChannelName={resolvedChannel.name}
           unarchiveChannelMutation={unarchiveChannelMutation}
         />
diff --git a/desktop/src/features/messages/lib/canManageMessage.ts b/desktop/src/features/messages/lib/canManageMessage.ts
new file mode 100644
index 0000000000..4b44ec7186
--- /dev/null
+++ b/desktop/src/features/messages/lib/canManageMessage.ts
@@ -0,0 +1,30 @@
+import { KIND_HUDDLE_STARTED } from "@/shared/constants/kinds";
+import { normalizePubkey } from "@/shared/lib/pubkey";
+import type { TimelineMessage } from "@/features/messages/types";
+import type { UserProfileLookup } from "@/features/profile/lib/identity";
+import { ownsAuthorAgent } from "@/features/profile/lib/identity";
+
+/**
+ * Returns true when the current user may edit or delete `message`.
+ *
+ * Two paths grant permission — mirroring the relay's authz:
+ *   1. Self-author: the current user pubkey matches the message pubkey.
+ *   2. Owner-of-agent: the message author's profile carries an `ownerPubkey`
+ *      (NIP-OA owner record) equal to the current user's pubkey.
+ *
+ * Huddle-started messages are immutable regardless of authorship.
+ */
+export function canManageMessageForCurrentUser(
+  message: TimelineMessage,
+  currentPubkey: string | undefined,
+  profiles: UserProfileLookup | undefined,
+): boolean {
+  if (message.kind === KIND_HUDDLE_STARTED) return false;
+  if (!currentPubkey || !message.pubkey) return false;
+  if (normalizePubkey(message.pubkey) === normalizePubkey(currentPubkey))
+    return true;
+  return ownsAuthorAgent(
+    profiles?.[normalizePubkey(message.pubkey)],
+    currentPubkey,
+  );
+}
diff --git a/desktop/src/features/messages/ui/MessageThreadPanel.tsx b/desktop/src/features/messages/ui/MessageThreadPanel.tsx
index 15d3ef3680..a146c76cea 100644
--- a/desktop/src/features/messages/ui/MessageThreadPanel.tsx
+++ b/desktop/src/features/messages/ui/MessageThreadPanel.tsx
@@ -7,6 +7,7 @@ import {
   type MainTimelineEntry,
 } from "@/features/messages/lib/threadPanel";
 import type { ImetaMedia } from "@/features/messages/lib/imetaMediaMarkdown";
+import { canManageMessageForCurrentUser } from "@/features/messages/lib/canManageMessage";
 import type { TimelineMessage } from "@/features/messages/types";
 import type { UserProfileLookup } from "@/features/profile/lib/identity";
 import type { Channel } from "@/shared/api/types";
@@ -103,17 +104,6 @@ type MessageThreadPanelSkeletonProps = {
   transparentChrome?: boolean;
 };
 
-function canManageMessage(
-  message: TimelineMessage,
-  currentPubkey: string | undefined,
-): boolean {
-  return Boolean(
-    currentPubkey &&
-      message.pubkey &&
-      currentPubkey.toLowerCase() === message.pubkey.toLowerCase(),
-  );
-}
-
 function hasLaterVisibleSibling(
   entries: readonly MainTimelineEntry[],
   entryIndex: number,
@@ -583,12 +573,22 @@ export function MessageThreadPanel({
               layoutVariant="thread-reply"
               message={threadHead}
               onDelete={
-                onDelete && canManageMessage(threadHead, currentPubkey)
+                onDelete &&
+                canManageMessageForCurrentUser(
+                  threadHead,
+                  currentPubkey,
+                  profiles,
+                )
                   ? onDelete
                   : undefined
               }
               onEdit={
-                onEdit && canManageMessage(threadHead, currentPubkey)
+                onEdit &&
+                canManageMessageForCurrentUser(
+                  threadHead,
+                  currentPubkey,
+                  profiles,
+                )
                   ? onEdit
                   : undefined
               }
@@ -717,13 +717,21 @@ export function MessageThreadPanel({
                         }
                         onDelete={
                           onDelete &&
-                          canManageMessage(entry.message, currentPubkey)
+                          canManageMessageForCurrentUser(
+                            entry.message,
+                            currentPubkey,
+                            profiles,
+                          )
                             ? onDelete
                             : undefined
                         }
                         onEdit={
                           onEdit &&
-                          canManageMessage(entry.message, currentPubkey)
+                          canManageMessageForCurrentUser(
+                            entry.message,
+                            currentPubkey,
+                            profiles,
+                          )
                             ? onEdit
                             : undefined
                         }
diff --git a/desktop/src/features/messages/ui/TimelineMessageList.tsx b/desktop/src/features/messages/ui/TimelineMessageList.tsx
index 22ebe8cb4d..5819368771 100644
--- a/desktop/src/features/messages/ui/TimelineMessageList.tsx
+++ b/desktop/src/features/messages/ui/TimelineMessageList.tsx
@@ -14,9 +14,9 @@ import {
   hasVideoAttachment,
 } from "@/features/messages/lib/videoReviewContext";
 import type { TimelineMessage } from "@/features/messages/types";
+import { canManageMessageForCurrentUser } from "@/features/messages/lib/canManageMessage";
 import type { UserProfileLookup } from "@/features/profile/lib/identity";
 import type { ChannelType } from "@/shared/api/types";
-import { KIND_HUDDLE_STARTED } from "@/shared/constants/kinds";
 import { cn } from "@/shared/lib/cn";
 import { DayDivider } from "./DayDivider";
 import { MessageRow } from "./MessageRow";
@@ -335,21 +335,13 @@ function MessageRowItem({
   videoReviewContext,
 }: MessageRowItemProps) {
   const { message, summary } = entry;
-  const isMutableMessage = message.kind !== KIND_HUDDLE_STARTED;
-  const canDelete =
-    isMutableMessage &&
-    onDelete &&
-    currentPubkey &&
-    message.pubkey === currentPubkey
-      ? onDelete
-      : undefined;
-  const canEdit =
-    isMutableMessage &&
-    onEdit &&
-    currentPubkey &&
-    message.pubkey === currentPubkey
-      ? onEdit
-      : undefined;
+  const canManage = canManageMessageForCurrentUser(
+    message,
+    currentPubkey,
+    profiles,
+  );
+  const canDelete = canManage && onDelete ? onDelete : undefined;
+  const canEdit = canManage && onEdit ? onEdit : undefined;
 
   if (summary && onReply) {
     const isHighlighted = message.id === highlightedMessageId;
diff --git a/desktop/src/features/profile/lib/identity.ts b/desktop/src/features/profile/lib/identity.ts
index 491883a0af..3093cebf61 100644
--- a/desktop/src/features/profile/lib/identity.ts
+++ b/desktop/src/features/profile/lib/identity.ts
@@ -85,6 +85,23 @@ export function resolveUserLabel(input: {
   return truncatePubkey(pubkey);
 }
 
+/**
+ * Returns true when the current user owns the agent that authored a message.
+ * Mirrors the relay's `is_agent_owner` gate: ownership is determined by the
+ * NIP-OA `ownerPubkey` field on the author's profile, NOT by the local
+ * managed-agents list (which can diverge from server-side ownership).
+ */
+export function ownsAuthorAgent(
+  profile: { ownerPubkey: string | null } | undefined,
+  currentPubkey: string | undefined,
+): boolean {
+  return (
+    !!currentPubkey &&
+    !!profile?.ownerPubkey &&
+    normalizePubkey(profile.ownerPubkey) === normalizePubkey(currentPubkey)
+  );
+}
+
 export function resolveUserSecondaryLabel(input: {
   pubkey: string;
   profiles?: UserProfileLookup;
diff --git a/desktop/src/testing/e2eBridge.ts b/desktop/src/testing/e2eBridge.ts
index bd590becbb..e4c6b99338 100644
--- a/desktop/src/testing/e2eBridge.ts
+++ b/desktop/src/testing/e2eBridge.ts
@@ -6235,6 +6235,23 @@ async function handleSendManagedAgentChannelMessage(
   };
 }
 
+/**
+ * Mock the `delete_message` Tauri command. Removes the event from the
+ * in-memory mock store so the query-cache invalidation in
+ * `useDeleteMessageMutation.onSuccess` (which filters by eventId) finds
+ * nothing to keep, and the row disappears from the timeline.
+ */
+function handleDeleteMessage(args: {
+  channelId: string;
+  eventId: string;
+}): void {
+  const history = mockMessages.get(args.channelId);
+  if (history) {
+    const index = history.findIndex((ev) => ev.id === args.eventId);
+    if (index !== -1) history.splice(index, 1);
+  }
+}
+
 /**
  * Mock the `edit_message` Tauri command. Mirrors the real Rust command
  * (`build_message_edit`): emit a kind:40003 edit event carrying `["e", target]`
@@ -7478,6 +7495,11 @@ export function maybeInstallE2eTauriMocks() {
           payload as Parameters<typeof handleSendManagedAgentChannelMessage>[0],
           activeConfig,
         );
+      case "delete_message":
+        handleDeleteMessage(
+          payload as Parameters<typeof handleDeleteMessage>[0],
+        );
+        return null;
       case "edit_message":
         return handleEditMessage(
           payload as Parameters<typeof handleEditMessage>[0],
diff --git a/desktop/tests/e2e/human-edit-agent-content.spec.ts b/desktop/tests/e2e/human-edit-agent-content.spec.ts
new file mode 100644
index 0000000000..93bc136217
--- /dev/null
+++ b/desktop/tests/e2e/human-edit-agent-content.spec.ts
@@ -0,0 +1,284 @@
+import { expect, test } from "@playwright/test";
+
+import { installMockBridge } from "../helpers/bridge";
+
+// Fixed pubkey for the owned managed agent seeded in these tests.
+// Must not collide with any existing e2eBridge constant.
+const OWNED_AGENT_PUBKEY =
+  "a0b1c2d3e4f5061728394a5b6c7d8e9f0a1b2c3d4e5f6071829304a5b6c7d8e";
+
+// #random is owned by alice; the mock identity is a plain member.
+// This is the isolation fixture for the canManageOwnedAgentChannel path —
+// selfMember.role is "member" not "owner", so without the new gate the
+// Edit button would not appear.
+const RANDOM_CHANNEL_ID = "9dae0116-799b-5071-a0a8-fdd30a91a35d";
+
+// Mock-bridge helper: wait for the bridge to initialise, then invoke a command.
+async function invoke(
+  page: import("@playwright/test").Page,
+  command: string,
+  payload?: Record<string, unknown>,
+): Promise<unknown> {
+  await page.waitForFunction(() =>
+    Boolean(
+      (
+        window as Window & {
+          __BUZZ_E2E_INVOKE_MOCK_COMMAND__?: unknown;
+        }
+      ).__BUZZ_E2E_INVOKE_MOCK_COMMAND__,
+    ),
+  );
+  return page.evaluate(
+    async ({ cmd, p }) => {
+      const win = window as Window & {
+        __BUZZ_E2E_INVOKE_MOCK_COMMAND__?: (
+          command: string,
+          payload?: Record<string, unknown>,
+        ) => Promise<unknown>;
+      };
+      const fn = win.__BUZZ_E2E_INVOKE_MOCK_COMMAND__;
+      if (!fn) throw new Error("Mock bridge unavailable");
+      return fn(cmd, p);
+    },
+    { cmd: command, p: payload },
+  );
+}
+
+// Open the more-actions menu for a message row and wait for the menu to mount.
+async function openMoreActionsMenu(
+  page: import("@playwright/test").Page,
+  messageId: string,
+) {
+  const row = page.locator(`[data-message-id="${messageId}"]`);
+  await row.hover();
+  await page.getByTestId(`more-actions-${messageId}`).click();
+  // Wait for dropdown content to mount — any menu item signals it's open.
+  await expect(page.locator('[role="menuitem"]').first()).toBeVisible({
+    timeout: 5_000,
+  });
+}
+
+test.beforeEach(async ({ page }) => {
+  await installMockBridge(page, {
+    managedAgents: [
+      {
+        // OwnedBot: a managed agent owned by the mock identity.
+        // The bridge automatically sets owner_pubkey = MOCK_IDENTITY_PUBKEY
+        // in mockProfiles when a managed agent is seeded.
+        pubkey: OWNED_AGENT_PUBKEY,
+        name: "OwnedBot",
+        personaId: "builtin:fizz",
+        status: "running",
+        // Seed into #agents so the bridge seeds a message from this agent.
+        channelNames: ["agents"],
+      },
+    ],
+  });
+});
+
+// ─── Message gate ─────────────────────────────────────────────────────────────
+
+test("owner can edit their owned agent's message", async ({ page }) => {
+  // The bridge seeds a message from each managed agent in its channels:
+  //   id: `mock-agents-managed-${pubkey.slice(0, 8)}`
+  const messageId = `mock-agents-managed-${OWNED_AGENT_PUBKEY.slice(0, 8)}`;
+  const editedContent = `Edited by owner ${Date.now()}`;
+
+  await page.goto("/");
+  await page.getByTestId("channel-agents").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("agents");
+
+  // Wait for the agent's seeded message to appear.
+  const agentRow = page.locator(`[data-message-id="${messageId}"]`);
+  await expect(agentRow).toBeVisible({ timeout: 10_000 });
+
+  // Open the more-actions menu and click Edit message.
+  await openMoreActionsMenu(page, messageId);
+  await page.getByTestId(`edit-message-${messageId}`).click();
+
+  // Edit banner must appear confirming edit mode is active.
+  await expect(page.getByTestId("edit-target")).toBeVisible({ timeout: 5_000 });
+
+  // Clear the composer and type the new content, then submit.
+  const input = page.getByTestId("message-input");
+  await input.clear();
+  await input.fill(editedContent);
+  await input.press("Enter");
+
+  // Edit mode must exit (banner gone) and the updated content must render.
+  await expect(page.getByTestId("edit-target")).toBeHidden();
+  await expect(page.getByTestId("message-timeline")).toContainText(
+    editedContent,
+  );
+});
+
+test("owner can delete their owned agent's message", async ({ page }) => {
+  const messageId = `mock-agents-managed-${OWNED_AGENT_PUBKEY.slice(0, 8)}`;
+
+  await page.goto("/");
+  await page.getByTestId("channel-agents").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("agents");
+
+  const agentRow = page.locator(`[data-message-id="${messageId}"]`);
+  await expect(agentRow).toBeVisible({ timeout: 10_000 });
+
+  // Open the more-actions menu and click Delete message.
+  await openMoreActionsMenu(page, messageId);
+  await page.getByTestId(`delete-message-${messageId}`).click();
+
+  // Confirm the deletion in the AlertDialog.
+  await expect(page.getByRole("alertdialog")).toBeVisible({ timeout: 5_000 });
+  // The destructive confirm button inside the dialog.
+  await page
+    .getByRole("alertdialog")
+    .getByRole("button", { name: "Delete" })
+    .click();
+
+  // The message row must be removed from the timeline.
+  await expect(agentRow).toBeHidden({ timeout: 5_000 });
+});
+
+test("owner does NOT see Edit or Delete for an unowned agent's message", async ({
+  page,
+}) => {
+  // "mock-agents-charlie" is seeded in #agents for CHARLIE_PUBKEY.
+  // Charlie is in mockAgentPubkeys but ownerPubkey is NOT the mock identity.
+  const charlieMessageId = "mock-agents-charlie";
+
+  await page.goto("/");
+  await page.getByTestId("channel-agents").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("agents");
+
+  const charlieRow = page.locator(`[data-message-id="${charlieMessageId}"]`);
+  await expect(charlieRow).toBeVisible({ timeout: 10_000 });
+
+  // Open the more-actions menu — it must open without Edit or Delete items.
+  await charlieRow.hover();
+  await page.getByTestId(`more-actions-${charlieMessageId}`).click();
+  await expect(page.locator('[role="menuitem"]').first()).toBeVisible({
+    timeout: 5_000,
+  });
+
+  await expect(
+    page.getByTestId(`edit-message-${charlieMessageId}`),
+  ).toHaveCount(0);
+  await expect(
+    page.getByTestId(`delete-message-${charlieMessageId}`),
+  ).toHaveCount(0);
+});
+
+// ─── Thread-panel gate ────────────────────────────────────────────────────────
+
+test("owner can delete their owned agent's message from the thread panel", async ({
+  page,
+}) => {
+  // The bridge seeds a message from each managed agent in its channels:
+  //   id: `mock-agents-managed-${pubkey.slice(0, 8)}`
+  const messageId = `mock-agents-managed-${OWNED_AGENT_PUBKEY.slice(0, 8)}`;
+
+  await page.goto("/");
+  await page.getByTestId("channel-agents").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("agents");
+
+  // Wait for the agent's seeded message to appear in the main timeline.
+  const agentRow = page.locator(`[data-message-id="${messageId}"]`).first();
+  await expect(agentRow).toBeVisible({ timeout: 10_000 });
+
+  // Open the thread panel by hovering the message and clicking Reply.
+  await agentRow.hover();
+  await agentRow.getByRole("button", { name: "Reply" }).click();
+
+  // Wait for the thread panel and confirm the thread head contains the agent message.
+  const threadPanel = page.getByTestId("message-thread-panel");
+  await expect(threadPanel).toBeVisible({ timeout: 5_000 });
+  const threadHead = threadPanel.getByTestId("message-thread-head");
+  await expect(
+    threadHead.locator(`[data-message-id="${messageId}"]`),
+  ).toBeVisible({
+    timeout: 5_000,
+  });
+
+  // Open the more-actions menu for the thread head from inside the thread panel.
+  const headRow = threadHead.locator(`[data-message-id="${messageId}"]`);
+  await headRow.hover();
+  await threadHead.getByTestId(`more-actions-${messageId}`).click();
+  // Wait for the dropdown to mount.
+  await expect(page.locator('[role="menuitem"]').first()).toBeVisible({
+    timeout: 5_000,
+  });
+
+  // Click Delete.
+  // Radix dropdown portals render outside the thread-panel DOM boundary, so we
+  // query from the full page. Only one menu is open, making the testId unique.
+  await page.getByTestId(`delete-message-${messageId}`).click();
+
+  // The AlertDialog must appear. This proves canManageMessageForCurrentUser is
+  // wired into MessageThreadPanel.tsx — the delete handler is reachable from
+  // the thread-panel path (i.e. the thread-panel permission gate is not
+  // accidentally more restrictive than the main-timeline gate). The full
+  // delete-and-cache-invalidation path is already covered by the main-timeline
+  // delete test above; asserting the dialog here is sufficient as a thread-panel
+  // regression guard.
+  await expect(page.getByRole("alertdialog")).toBeVisible({ timeout: 5_000 });
+
+  // Dismiss without confirming — leaves the fixture clean for any subsequent steps.
+  await page.keyboard.press("Escape");
+  await expect(page.getByRole("alertdialog")).not.toBeVisible({
+    timeout: 3_000,
+  });
+});
+
+// ─── Channel management gate ──────────────────────────────────────────────────
+
+test("owner can edit channel name via owned-agent-owner path", async ({
+  page,
+}) => {
+  const newChannelName = `renamed-${Date.now()}`;
+
+  await page.goto("/");
+
+  // Add OwnedBot as an owner-role member of #random.
+  // In #random the mock identity is only a plain member — selfMember.role !== "owner".
+  // This isolates canManageOwnedAgentChannel as the sole reason Edit appears.
+  await invoke(page, "add_channel_members", {
+    channelId: RANDOM_CHANNEL_ID,
+    pubkeys: [OWNED_AGENT_PUBKEY],
+    role: "owner",
+  });
+
+  await page.getByTestId("channel-random").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("random");
+  await page.getByTestId("channel-management-trigger").click();
+  await expect(page.getByTestId("channel-management-sheet")).toBeVisible();
+
+  // Edit quick-action must be visible: canManageOwnedAgentChannel is true.
+  const editButton = page.getByTestId("channel-management-edit");
+  await expect(editButton).toBeVisible({ timeout: 5_000 });
+  await editButton.click();
+
+  // Change the channel name and save.
+  const nameInput = page.getByTestId("channel-management-name");
+  await expect(nameInput).toBeVisible({ timeout: 5_000 });
+  await nameInput.clear();
+  await nameInput.fill(newChannelName);
+  await page.getByTestId("channel-management-save-changes").click();
+
+  // The edit dialog must close and the updated name must appear in the header.
+  await expect(page.getByTestId("channel-management-name")).toBeHidden();
+  await expect(page.getByTestId("chat-title")).toHaveText(newChannelName);
+});
+
+test("owner does NOT see channel Edit button when no owned agent is a channel owner", async ({
+  page,
+}) => {
+  await page.goto("/");
+
+  // #random has alice as owner; mock identity is a plain member.
+  // OwnedBot is NOT added as owner in this test — Edit must not appear.
+  await page.getByTestId("channel-random").click();
+  await expect(page.getByTestId("chat-title")).toHaveText("random");
+  await page.getByTestId("channel-management-trigger").click();
+  await expect(page.getByTestId("channel-management-sheet")).toBeVisible();
+
+  await expect(page.getByTestId("channel-management-edit")).toBeHidden();
+});