fix(start-work): reuse registered opencode agent names

src/hooks/atlas/boulder-continuation-injector.ts

@@ -1,6 +1,9 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import type { BackgroundManager } from "../../features/background-agent"
-import { isAgentRegistered } from "../../features/claude-code-session-state"
+import {
+  isAgentRegistered,
+  resolveRegisteredAgentName,
+} from "../../features/claude-code-session-state"
 import { log } from "../../shared/logger"
 import { createInternalAgentTextPart, resolveInheritedPromptTools } from "../../shared"
 import { HOOK_NAME } from "./hook-name"
@@ -55,7 +58,9 @@ export async function injectBoulderContinuation(input: {
 		`\n\n[Status: ${total - remaining}/${total} completed, ${remaining} remaining]` +
 		preferredSessionContext +
 		worktreeContext
-	const continuationAgent = (agent ?? (isAgentRegistered("atlas") ? "atlas" : undefined))?.replace(/\u200B/g, "")
+	const continuationAgent = resolveRegisteredAgentName(
+		agent ?? (isAgentRegistered("atlas") ? "atlas" : undefined),
+	)
 
 	if (!continuationAgent || !isAgentRegistered(continuationAgent)) {
 		log(`[${HOOK_NAME}] Skipped injection: continuation agent unavailable`, {

src/hooks/compaction-context-injector/recovery.ts

@@ -1,4 +1,7 @@
-import { updateSessionAgent } from "../../features/claude-code-session-state"
+import {
+  resolveRegisteredAgentName,
+  updateSessionAgent,
+} from "../../features/claude-code-session-state"
 import {
   getCompactionAgentConfigCheckpoint,
 } from "../../shared/compaction-agent-config-checkpoint"
@@ -66,6 +69,7 @@ export function createRecoveryLogic(
       checkpointWithAgent,
       currentPromptConfig,
     )
+    const launchAgent = resolveRegisteredAgentName(expectedPromptConfig.agent)
     const model = expectedPromptConfig.model
     const tools = expectedPromptConfig.tools
 
@@ -81,7 +85,7 @@ export function createRecoveryLogic(
         path: { id: sessionID },
         body: {
           noReply: true,
-          agent: expectedPromptConfig.agent,
+          agent: launchAgent ?? expectedPromptConfig.agent,
           ...(model ? { model } : {}),
           ...(tools ? { tools } : {}),
           parts: [createInternalAgentTextPart(AGENT_RECOVERY_PROMPT)],

src/hooks/no-hephaestus-non-gpt/hook.ts

@@ -1,8 +1,12 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { isGptModel } from "../../agents/types"
-import { getSessionAgent, updateSessionAgent } from "../../features/claude-code-session-state"
+import {
+  getSessionAgent,
+  resolveRegisteredAgentName,
+  updateSessionAgent,
+} from "../../features/claude-code-session-state"
 import { log } from "../../shared"
-import { getAgentConfigKey, getAgentDisplayName } from "../../shared/agent-display-names"
+import { getAgentConfigKey } from "../../shared/agent-display-names"
 
 const TOAST_TITLE = "NEVER Use Hephaestus with Non-GPT"
 const TOAST_MESSAGE = [
@@ -10,8 +14,6 @@ const TOAST_MESSAGE = [
   "Hephaestus is trash without GPT.",
   "For Claude/Kimi/GLM models, always use Sisyphus.",
 ].join("\n")
-const SISYPHUS_DISPLAY = getAgentDisplayName("sisyphus")
-
 type NoHephaestusNonGptHookOptions = {
   allowNonGptModel?: boolean
 }
@@ -54,9 +56,9 @@ export function createNoHephaestusNonGptHook(
         if (allowNonGptModel) {
           return
         }
-        input.agent = "sisyphus"
+        input.agent = resolveRegisteredAgentName("sisyphus") ?? "sisyphus"
         if (output?.message) {
-          output.message.agent = "sisyphus"
+          output.message.agent = resolveRegisteredAgentName("sisyphus") ?? "sisyphus"
         }
         updateSessionAgent(input.sessionID, "sisyphus")
       }

src/hooks/no-sisyphus-gpt/hook.ts

@@ -1,8 +1,12 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 import { isGptModel, isGpt5_4Model } from "../../agents/types"
-import { getSessionAgent, updateSessionAgent } from "../../features/claude-code-session-state"
+import {
+  getSessionAgent,
+  resolveRegisteredAgentName,
+  updateSessionAgent,
+} from "../../features/claude-code-session-state"
 import { log } from "../../shared"
-import { getAgentConfigKey, getAgentDisplayName } from "../../shared/agent-display-names"
+import { getAgentConfigKey } from "../../shared/agent-display-names"
 
 const TOAST_TITLE = "NEVER Use Sisyphus with GPT"
 const TOAST_MESSAGE = [
@@ -10,8 +14,6 @@ const TOAST_MESSAGE = [
   "Do NOT use Sisyphus with GPT (except GPT-5.4 which has specialized support).",
   "For GPT models (other than 5.4), always use Hephaestus.",
 ].join("\n")
-const HEPHAESTUS_DISPLAY = getAgentDisplayName("hephaestus")
-
 function showToast(ctx: PluginInput, sessionID: string): void {
   ctx.client.tui.showToast({
     body: {
@@ -43,9 +45,9 @@ export function createNoSisyphusGptHook(ctx: PluginInput) {
 
       if (agentKey === "sisyphus" && modelID && isGptModel(modelID) && !isGpt5_4Model(modelID)) {
         showToast(ctx, input.sessionID)
-        input.agent = "hephaestus"
+        input.agent = resolveRegisteredAgentName("hephaestus") ?? "hephaestus"
         if (output?.message) {
-          output.message.agent = "hephaestus"
+          output.message.agent = resolveRegisteredAgentName("hephaestus") ?? "hephaestus"
         }
         updateSessionAgent(input.sessionID, "hephaestus")
       }

src/hooks/runtime-fallback/auto-retry.ts

@@ -9,7 +9,7 @@ import { SessionCategoryRegistry } from "../../shared/session-category-registry"
 import { buildRetryModelPayload } from "./retry-model-payload"
 import { getLastUserRetryParts } from "./last-user-retry-parts"
 import { extractSessionMessages } from "./session-messages"
-import { getAgentDisplayName } from "../../shared/agent-display-names"
+import { resolveRegisteredAgentName } from "../../features/claude-code-session-state"
 
 const SESSION_TTL_MS = 30 * 60 * 1000
 
@@ -133,14 +133,14 @@ export function createAutoRetryHelpers(deps: HookDeps) {
         })
 
         const retryAgent = resolvedAgent ?? getSessionAgent(sessionID)
+        const launchAgent = resolveRegisteredAgentName(retryAgent)
         sessionAwaitingFallbackResult.add(sessionID)
         scheduleSessionFallbackTimeout(sessionID, retryAgent)
 
         await ctx.client.session.promptAsync({
           path: { id: sessionID },
           body: {
-            // Use config key to avoid HTTP header validation issues with display names
-            ...(retryAgent ? { agent: retryAgent } : {}),
+            ...(launchAgent ? { agent: launchAgent } : {}),
             ...retryModelPayload,
             parts: retryParts,
           },

src/hooks/start-work/start-work-hook.ts

@@ -13,6 +13,7 @@ import {
 import { log } from "../../shared/logger"
 import {
   isAgentRegistered,
+  resolveRegisteredAgentName,
   updateSessionAgent,
 } from "../../features/claude-code-session-state"
 import { detectWorktreePath } from "./worktree-detector"
@@ -83,7 +84,7 @@ export function createStartWorkHook(ctx: PluginInput) {
       : "sisyphus"
     updateSessionAgent(input.sessionID, activeAgent)
     if (output.message) {
-      output.message["agent"] = activeAgent
+      output.message["agent"] = resolveRegisteredAgentName(activeAgent) ?? activeAgent
     }
 
     const existingState = readBoulderState(ctx.directory)

src/hooks/todo-continuation-enforcer/continuation-injection.test.ts

@@ -5,7 +5,7 @@ import { injectContinuation } from "./continuation-injection"
 import { OMO_INTERNAL_INITIATOR_MARKER } from "../../shared/internal-initiator-marker"
 
 describe("injectContinuation", () => {
-  test("normalizes built-in display names to config keys before promptAsync", async () => {
+  test("preserves the registered built-in agent name before promptAsync", async () => {
     // given
     let capturedAgent: string | undefined
     const ctx = {
@@ -40,7 +40,7 @@ describe("injectContinuation", () => {
     })
 
     // then
-    expect(capturedAgent).toBe("sisyphus")
+    expect(capturedAgent).toBe("Sisyphus - Ultraworker")
   })
 
   test("inherits tools from resolved message info when reinjecting", async () => {

src/hooks/todo-continuation-enforcer/continuation-injection.ts

@@ -1,7 +1,10 @@
 import type { PluginInput } from "@opencode-ai/plugin"
 
 import type { BackgroundManager } from "../../features/background-agent"
-import { getSessionAgent } from "../../features/claude-code-session-state"
+import {
+  getSessionAgent,
+  resolveRegisteredAgentName,
+} from "../../features/claude-code-session-state"
 import {
   createInternalAgentTextPart,
   normalizeSDKResponse,
@@ -127,6 +130,7 @@ export async function injectContinuation(args: {
   }
 
   const promptAgent = normalizeAgentForPromptKey(agentName)
+  const launchAgent = resolveRegisteredAgentName(agentName)
 
   if (promptAgent && skipAgents.some(s => getAgentConfigKey(s) === getAgentConfigKey(promptAgent))) {
     log(`[${HOOK_NAME}] Skipped: agent in skipAgents list`, { sessionID, agent: agentName })
@@ -168,7 +172,7 @@ ${todoList}`
   try {
     log(`[${HOOK_NAME}] Injecting continuation`, {
       sessionID,
-      agent: promptAgent,
+      agent: launchAgent ?? promptAgent,
       model,
       incompleteCount: freshIncompleteCount,
     })
@@ -183,7 +187,7 @@ ${todoList}`
     await ctx.client.session.promptAsync({
       path: { id: sessionID },
       body: {
-        agent: promptAgent,
+        agent: launchAgent ?? promptAgent,
         ...(launchModel ? { model: launchModel } : {}),
         ...(launchVariant ? { variant: launchVariant } : {}),
         ...(inheritedTools ? { tools: inheritedTools } : {}),