fix: reject unsupported skill fields

crates/worker/src/worker.rs

@@ -5968,6 +5968,102 @@ mod build_summary_prompt_tests {
         assert!(!prompt.contains("resident summary marker"));
     }
 
+    #[test]
+    fn activate_skill_commits_and_appends_history_before_future_context_use() {
+        use std::io::{BufRead, BufReader, Write};
+        use std::net::TcpListener;
+        use std::thread;
+
+        let listener = TcpListener::bind("127.0.0.1:0").unwrap();
+        let addr = listener.local_addr().unwrap();
+        let server = thread::spawn(move || {
+            let (mut stream, _) = listener.accept().unwrap();
+            let mut reader = BufReader::new(stream.try_clone().unwrap());
+            let mut request_line = String::new();
+            reader.read_line(&mut request_line).unwrap();
+            assert!(
+                request_line
+                    .starts_with("GET /api/w/ws-skill/skills/triage-errors/activate HTTP/1.1")
+            );
+            loop {
+                let mut line = String::new();
+                reader.read_line(&mut line).unwrap();
+                if line == "\r\n" || line.is_empty() {
+                    break;
+                }
+            }
+            let body = serde_json::json!({
+                "name": "triage-errors",
+                "provenance": { "kind": "workspace", "id": "workspace:triage-errors" },
+                "diagnostics": [],
+                "body": "---\nname: triage-errors\ndescription: Use when testing activation history.\n---\n\n# Triage Errors\n\nCommitted Skill body."
+            })
+            .to_string();
+            write!(
+                stream,
+                "HTTP/1.1 200 OK\r\ncontent-type: application/json\r\ncontent-length: {}\r\n\r\n{}",
+                body.len(),
+                body
+            )
+            .unwrap();
+        });
+
+        let dir = tempfile::tempdir().unwrap();
+        let manifest = minimal_manifest();
+        let store = session_store::FsStore::new(dir.path().join("sessions")).unwrap();
+        let cwd = dir.path().join("workspace");
+        std::fs::create_dir_all(&cwd).unwrap();
+        let scope = Scope::writable(&cwd).unwrap();
+        let authority = WorkerFilesystemAuthority::local(cwd.clone(), cwd.clone());
+        let mut worker = tokio::runtime::Runtime::new()
+            .unwrap()
+            .block_on(Worker::new(
+                manifest,
+                Engine::new(NoopClient),
+                store,
+                WorkerWorkspaceContext::with_client(
+                    Some(WorkspaceId::new("ws-skill").unwrap()),
+                    WorkspaceClient::http("ws-skill", format!("http://{addr}")),
+                ),
+                authority,
+                scope,
+            ))
+            .unwrap();
+
+        let activation = worker.activate_skill("triage-errors").unwrap();
+
+        assert_eq!(activation.name, "triage-errors");
+        server.join().unwrap();
+        let history = worker.history();
+        assert_eq!(history.len(), 1);
+        let history_text = history[0].as_text().unwrap();
+        assert!(
+            history_text
+                .contains("Agent Skill `triage-errors` activated from workspace:triage-errors")
+        );
+        assert!(history_text.contains("# Triage Errors"));
+        assert!(history_text.contains("Committed Skill body."));
+
+        let entries = worker
+            .store
+            .read_all(
+                worker.segment_state.session_id(),
+                worker.segment_state.segment_id(),
+            )
+            .unwrap();
+        assert!(entries.iter().any(|entry| {
+            matches!(
+                entry,
+                LogEntry::SystemItem {
+                    item: SystemItem::SkillActivation { name, body },
+                    ..
+                } if name == "triage-errors"
+                    && body.contains("# Triage Errors")
+                    && body == history_text
+            )
+        }));
+    }
+
     fn minimal_manifest() -> WorkerManifest {
         let toml_str = r#"
 [worker]