test: add stable json output fixtures

crates/geth/tests/bootstrap.rs

@@ -32,6 +32,40 @@ fn run_geth(home: &std::path::Path, args: &[&str]) -> std::process::Output {
         .expect("run geth")
 }
 
+fn json_fixture(name: &str) -> serde_json::Value {
+    let path = std::path::Path::new(env!("CARGO_MANIFEST_DIR"))
+        .join("tests/fixtures/json")
+        .join(name);
+    serde_json::from_str(&std::fs::read_to_string(&path).expect("read json fixture"))
+        .expect("decode json fixture")
+}
+
+fn command_json(output: &std::process::Output) -> serde_json::Value {
+    assert!(
+        output.status.success(),
+        "stderr: {}",
+        String::from_utf8_lossy(&output.stderr)
+    );
+    serde_json::from_slice(&output.stdout).expect("decode command json")
+}
+
+fn normalize_node_id_json(mut value: serde_json::Value) -> serde_json::Value {
+    let object = value.as_object_mut().expect("node id json object");
+    object.insert(
+        "agent_id".to_owned(),
+        serde_json::Value::String("agent:<normalized>".to_owned()),
+    );
+    object.insert(
+        "node_id".to_owned(),
+        serde_json::Value::String("node:<normalized>".to_owned()),
+    );
+    object.insert(
+        "endpoint_id".to_owned(),
+        serde_json::Value::String("<endpoint-id>".to_owned()),
+    );
+    value
+}
+
 fn spawn_daemon(home: &std::path::Path) -> Child {
     Command::new(geth_bin())
         .env("GETH_HOME", home)
@@ -248,6 +282,43 @@ fn geth_status_against_running_daemon() {
     ));
 }
 
+#[test]
+fn stable_json_output_matches_fixtures() {
+    let home = tempfile::tempdir().expect("tempdir");
+    if !unix_sockets_available(home.path()) {
+        return;
+    }
+    assert!(run_geth(home.path(), &["init"]).status.success());
+    std::fs::write(
+        home.path().join("config.toml"),
+        "[iroh]\nrelay_mode = \"disabled\"\nlocal_discovery = false\n",
+    )
+    .expect("write config");
+
+    let mut daemon = spawn_daemon(home.path());
+    wait_for_socket(&home.path().join("run/geth.sock"));
+
+    let node_id = run_geth(home.path(), &["--json", "node", "id"]);
+    let resource_list = run_geth(home.path(), &["--json", "resource", "list"]);
+    let sync_status = run_geth(home.path(), &["--json", "sync", "status"]);
+
+    let _ = daemon.kill();
+    let _ = daemon.wait();
+
+    assert_eq!(
+        normalize_node_id_json(command_json(&node_id)),
+        json_fixture("node-id.json")
+    );
+    assert_eq!(
+        command_json(&resource_list),
+        json_fixture("resource-list-fresh.json")
+    );
+    assert_eq!(
+        command_json(&sync_status),
+        json_fixture("sync-status-empty.json")
+    );
+}
+
 #[test]
 fn peer_ping_uses_daemon_owned_iroh_endpoint() {
     if skip_iroh_integration_tests() {

crates/geth/tests/fixtures/json/README.md

@@ -0,0 +1,9 @@
+# JSON Fixtures
+
+These fixtures define reviewed, script-facing `geth --json` shapes. Tests may
+normalize volatile local values such as generated node IDs, agent IDs, endpoint
+IDs, and temporary paths before comparing output.
+
+Changing a fixture is a compatibility decision. Update the matching roadmap
+item and compatibility notes when a stable field is added, removed, renamed, or
+retyped.

crates/geth/tests/fixtures/json/node-id.json

@@ -0,0 +1,6 @@
+{
+  "type": "node-id",
+  "agent_id": "agent:<normalized>",
+  "node_id": "node:<normalized>",
+  "endpoint_id": "<endpoint-id>"
+}

crates/geth/tests/fixtures/json/resource-list-fresh.json

@@ -0,0 +1,17 @@
+{
+  "type": "resource-list",
+  "resources": [
+    {
+      "id": "resource:cas:local",
+      "kind": "cas",
+      "name": "local-cas",
+      "authority": {
+        "kind": "local"
+      },
+      "local_role": "owner",
+      "replication": "local-only",
+      "retention": "keep",
+      "status": "active"
+    }
+  ]
+}

crates/geth/tests/fixtures/json/sync-status-empty.json

@@ -0,0 +1,5 @@
+{
+  "type": "sync-status",
+  "peers": [],
+  "note": "sync status is local daemon health for best-effort live sync; signed logs remain the durable source of truth"
+}

docs/production-readiness-roadmap.md

@@ -79,7 +79,7 @@ behavior.
   - `[x]` Sync stream selection, watermarks, and run result helpers live in a
     sync-focused module.
   - `[x]` Per-module sync handlers have consistent interfaces.
-  - `[ ]` `geth sync status --json` output remains stable.
+  - `[x]` `geth sync status --json` output remains stable.
 
 ## Phase 2: Stable Automation Contracts
 
@@ -94,12 +94,12 @@ and downstream projects.
   - `[x]` Peer wire protocol compatibility is documented.
   - `[x]` SQLite and signed-operation compatibility are documented.
 
-- `[ ]` Add golden JSON tests.
+- `[~]` Add golden JSON tests.
   Acceptance criteria:
-  - `[ ]` Important script-facing commands have stable JSON fixture tests.
+  - `[x]` Important script-facing commands have stable JSON fixture tests.
   - `[ ]` Error JSON includes stable codes for common operator and automation
     failures.
-  - `[ ]` Fixture updates require intentional review.
+  - `[x]` Fixture updates require intentional review.
 
 - `[~]` Expand protocol roundtrip tests.
   Acceptance criteria: