feat(#1178): add kill + update tools to AgentServer (topology-scoped)

hive-ag3nt/prompts/system.md

@@ -43,6 +43,8 @@ Tools (hyperhive surface):
 <!-- role:agent -->
 - `mcp__hyperhive__request_next_turn()` — ask the harness to start another turn immediately after this one ends, even if the inbox is empty. Use for multi-turn tasks (long builds, sequential steps) where you want to continue without waiting for an external message. The next turn starts with `from: "self"` and `body: "continue"`. No-op if new inbox messages arrive before this turn ends (the harness already loops immediately on pending messages). No args.
 - `mcp__hyperhive__restart(name)` — *(requires `lifecycle` tool group)* restart a direct child sub-agent (stop + start). The server enforces topology: the call is rejected unless `name` is a direct child of yours per `topology.json`. No approval required.
+- `mcp__hyperhive__kill(name)` — *(requires `lifecycle` tool group)* stop a direct child sub-agent (graceful). Direct children only — server enforces topology. State dir kept; recreating reuses prior config + credentials. No approval required.
+- `mcp__hyperhive__update(name)` — *(requires `lifecycle` tool group)* rebuild a direct child sub-agent: re-applies the current hyperhive flake + agent.nix and restarts it. Direct children only — server enforces topology. No approval required. Idempotent.
 
 Need new packages, env vars, or other NixOS config for yourself? You can't edit your own config directly — message the manager (recipient `root`) describing what you need + why. The manager evaluates the request (it doesn't rubber-stamp), edits `/agents/{label}/config/agent.nix` on your behalf, commits, and submits an approval that the operator can accept on the dashboard; on approve hive-c0re rebuilds your container with the new config.
 

hive-ag3nt/src/mcp.rs

@@ -966,6 +966,48 @@ impl AgentServer {
         .await
     }
 
+    // IMPORTANT: this tool is only available when the `lifecycle` tool group
+    // is granted to this agent. hive-c0re enforces the topology check
+    // server-side: the call is rejected unless `name` is a direct child.
+    #[tool(
+        description = "Stop a direct child sub-agent container (graceful). \
+            Only succeeds if `name` is a direct child of this agent in the topology \
+            tree — the server enforces this. No approval required. \
+            State dir is kept; recreating the agent reuses prior config + credentials."
+    )]
+    async fn kill(&self, Parameters(args): Parameters<KillArgs>) -> String {
+        let log = format!("{args:?}");
+        let name = args.name.clone();
+        run_tool_envelope("kill", log, async move {
+            let (resp, retries) = self
+                .dispatch(hive_sh4re::AgentRequest::Kill { name: args.name })
+                .await;
+            annotate_retries(format_ack(resp, "kill", format!("killed {name}")), retries)
+        })
+        .await
+    }
+
+    // IMPORTANT: this tool is only available when the `lifecycle` tool group
+    // is granted to this agent. hive-c0re enforces the topology check
+    // server-side: the call is rejected unless `name` is a direct child.
+    #[tool(
+        description = "Rebuild a direct child sub-agent: re-applies the current hyperhive \
+            flake + agent.nix and restarts the container. Only succeeds if `name` is a direct \
+            child of this agent in the topology tree — the server enforces this. \
+            No approval required. Idempotent — use when a child needs its config reapplied."
+    )]
+    async fn update(&self, Parameters(args): Parameters<UpdateArgs>) -> String {
+        let log = format!("{args:?}");
+        let name = args.name.clone();
+        run_tool_envelope("update", log, async move {
+            let (resp, retries) = self
+                .dispatch(hive_sh4re::AgentRequest::Update { name: args.name })
+                .await;
+            annotate_retries(format_ack(resp, "update", format!("updated {name}")), retries)
+        })
+        .await
+    }
+
     // IMPORTANT: this tool is capability-gated (`read_host_journal`).
     // It is added to `--allowedTools` by `allowed_capability_tools` only
     // when `HIVE_CAPABILITIES` contains `read_host_journal`. hive-c0re