feat(hooks): add ultrawork-model-override hook for per-agent model swap

src/hooks/index.ts

@@ -46,3 +46,5 @@ export { createPreemptiveCompactionHook } from "./preemptive-compaction";
 export { createTasksTodowriteDisablerHook } from "./tasks-todowrite-disabler";
 export { createWriteExistingFileGuardHook } from "./write-existing-file-guard";
 export { createHashlineReadEnhancerHook } from "./hashline-read-enhancer";
+
+export { createUltraworkModelOverrideHook } from "./ultrawork-model-override";

src/hooks/ultrawork-model-override/hook.ts

@@ -0,0 +1,83 @@
+import type { AgentOverrides } from "../../config"
+import { log } from "../../shared"
+import { getAgentConfigKey } from "../../shared/agent-display-names"
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null
+}
+
+function getUltraworkConfig(agents: AgentOverrides | undefined, configKey: string) {
+  if (!agents) return undefined
+
+  for (const [agentKey, override] of Object.entries(agents)) {
+    if (getAgentConfigKey(agentKey) === configKey) {
+      return override?.ultrawork
+    }
+  }
+
+  return undefined
+}
+
+export function createUltraworkModelOverrideHook(args: { agents?: AgentOverrides }) {
+  let didLogSpikeInput = false
+
+  return {
+    "chat.params": async (input: unknown, output: unknown): Promise<void> => {
+      if (!didLogSpikeInput) {
+        didLogSpikeInput = true
+
+        const inputRecord = isRecord(input) ? input : null
+        const messageRecord = isRecord(inputRecord?.message) ? inputRecord.message : null
+
+        log("ultrawork-model-override spike: raw chat.params input", {
+          inputType: typeof input,
+          outputType: typeof output,
+          hasMessage: messageRecord !== null,
+          messageKeys: messageRecord ? Object.keys(messageRecord) : [],
+          hasMessageModel: messageRecord ? "model" in messageRecord : false,
+          messageModelType: messageRecord ? typeof messageRecord.model : "undefined",
+        })
+      }
+
+      if (!isRecord(input)) return
+
+      const message = input.message
+      if (!isRecord(message)) return
+      if (message.variant !== "max") return
+
+      const agentName = input.agent
+      if (typeof agentName !== "string") return
+
+      const configKey = getAgentConfigKey(agentName)
+      const ultrawork = getUltraworkConfig(args.agents, configKey)
+      if (!ultrawork?.model) return
+
+      const separatorIndex = ultrawork.model.indexOf("/")
+      const providerID = separatorIndex === -1 ? ultrawork.model : ultrawork.model.slice(0, separatorIndex)
+      const modelID = separatorIndex === -1 ? "" : ultrawork.model.slice(separatorIndex + 1)
+
+      const previousModel = isRecord(message.model)
+        ? {
+            providerID:
+              typeof message.model.providerID === "string" ? message.model.providerID : undefined,
+            modelID: typeof message.model.modelID === "string" ? message.model.modelID : undefined,
+          }
+        : undefined
+
+      message.model = { providerID, modelID }
+
+      if (ultrawork.variant !== undefined) {
+        message.variant = ultrawork.variant
+      }
+
+      log("ultrawork-model-override: swapped model", {
+        sessionID: typeof input.sessionID === "string" ? input.sessionID : undefined,
+        agent: agentName,
+        configKey,
+        from: previousModel,
+        to: message.model,
+        variant: message.variant,
+      })
+    },
+  }
+}

src/hooks/ultrawork-model-override/index.ts

@@ -0,0 +1 @@
+export { createUltraworkModelOverrideHook } from "./hook"