fix: permanently resolve agent name duplication yo-yo bug

src/features/claude-code-session-state/state.test.ts

@@ -6,6 +6,8 @@ import {
   updateSessionAgent,
   setMainSession,
   getMainSessionID,
+  registerAgentName,
+  isAgentRegistered,
   _resetForTesting,
 } from "./state"
 
@@ -102,6 +104,17 @@ describe("claude-code-session-state", () => {
     })
   })
 
+  describe("agent registration", () => {
+    test("should register config-key lookup when given a display name", () => {
+      // given
+      registerAgentName("Atlas (Plan Executor)")
+
+      // when / then
+      expect(isAgentRegistered("atlas")).toBe(true)
+      expect(isAgentRegistered("Atlas (Plan Executor)")).toBe(true)
+    })
+  })
+
   describe("prometheus-md-only integration scenario", () => {
     test("should correctly identify Prometheus agent for permission checks", () => {
       // given - Prometheus session

src/features/claude-code-session-state/state.ts

@@ -1,3 +1,5 @@
+import { getAgentConfigKey } from "../../shared/agent-display-names"
+
 export const subagentSessions = new Set<string>()
 export const syncSubagentSessions = new Set<string>()
 
@@ -14,7 +16,13 @@ export function getMainSessionID(): string | undefined {
 const registeredAgentNames = new Set<string>()
 
 export function registerAgentName(name: string): void {
-  registeredAgentNames.add(name.toLowerCase())
+  const normalizedName = name.toLowerCase()
+  registeredAgentNames.add(normalizedName)
+
+  const configKey = getAgentConfigKey(name).toLowerCase()
+  if (configKey !== normalizedName) {
+    registeredAgentNames.add(configKey)
+  }
 }
 
 export function isAgentRegistered(name: string): boolean {

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

@@ -0,0 +1,54 @@
+import { describe, test, expect, beforeEach, afterEach, mock } from "bun:test"
+import type { PluginInput } from "@opencode-ai/plugin"
+import { registerAgentName, _resetForTesting } from "../../features/claude-code-session-state"
+import { injectBoulderContinuation } from "./boulder-continuation-injector"
+
+describe("injectBoulderContinuation", () => {
+  beforeEach(() => {
+    // given
+    _resetForTesting()
+  })
+
+  afterEach(() => {
+    // then
+    _resetForTesting()
+  })
+
+  test("normalizes config-key agent to display-name for promptAsync", async () => {
+    // given
+    registerAgentName("atlas")
+    const promptAsyncMock = mock(async (_request: unknown) => undefined)
+    const messagesMock = mock(async () => ({ data: [] }))
+
+    const ctx = {
+      directory: "/tmp",
+      client: {
+        session: {
+          messages: messagesMock,
+          promptAsync: promptAsyncMock,
+        },
+      },
+    } as unknown as PluginInput
+
+    // when
+    await injectBoulderContinuation({
+      ctx,
+      sessionID: "ses_test_123",
+      planName: "test-plan",
+      remaining: 1,
+      total: 2,
+      agent: "atlas",
+      sessionState: { promptFailureCount: 0 },
+    })
+
+    // then
+    expect(promptAsyncMock).toHaveBeenCalledTimes(1)
+    expect(promptAsyncMock).toHaveBeenCalledWith(
+      expect.objectContaining({
+        body: expect.objectContaining({
+          agent: "Atlas (Plan Executor)",
+        }),
+      }),
+    )
+  })
+})

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

@@ -1,9 +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 { normalizeAgentForPrompt } from "../../shared/agent-display-names"
 import { log } from "../../shared/logger"
 import { createInternalAgentTextPart, resolveInheritedPromptTools } from "../../shared"
-import { getAgentConfigKey } from "../../shared/agent-display-names"
 import { HOOK_NAME } from "./hook-name"
 import { BOULDER_CONTINUATION_PROMPT } from "./system-reminder-templates"
 import { resolveRecentPromptContextForSession } from "./recent-model-resolver"
@@ -73,7 +73,7 @@ export async function injectBoulderContinuation(input: {
 		await ctx.client.session.promptAsync({
 			path: { id: sessionID },
 			body: {
-				agent: getAgentConfigKey(continuationAgent),
+				agent: normalizeAgentForPrompt(continuationAgent) ?? continuationAgent,
 				...(promptContext.model !== undefined ? { model: promptContext.model } : {}),
 				...(inheritedTools ? { tools: inheritedTools } : {}),
         parts: [createInternalAgentTextPart(prompt)],

src/hooks/atlas/index.test.ts

@@ -1679,9 +1679,42 @@ session_id: ses_untrusted_999
        // then - should call prompt for sisyphus
        expect(mockInput._promptMock).toHaveBeenCalled()
        const callArgs = mockInput._promptMock.mock.calls[0][0]
-       expect(callArgs.body.agent).toBe("sisyphus")
+       expect(callArgs.body.agent).toBe("Sisyphus (Ultraworker)")
      })
 
+    test("should preserve display-name agent in continuation prompt when boulder agent uses display form", async () => {
+      // given - boulder state uses display-form agent name
+      const planPath = join(TEST_DIR, "test-plan.md")
+      writeFileSync(planPath, "# Plan\n- [ ] Task 1\n- [ ] Task 2")
+
+      const state: BoulderState = {
+        active_plan: planPath,
+        started_at: "2026-01-02T10:00:00Z",
+        session_ids: [MAIN_SESSION_ID],
+        plan_name: "test-plan",
+        agent: "Atlas (Plan Executor)",
+      }
+      writeBoulderState(TEST_DIR, state)
+      registerAgentName("Atlas (Plan Executor)")
+
+      const mockInput = createMockPluginInput()
+      const hook = createAtlasHook(mockInput)
+
+      // when
+      await hook.handler({
+        event: {
+          type: "session.idle",
+          properties: { sessionID: MAIN_SESSION_ID },
+        },
+      })
+
+      // then
+      expect(mockInput._promptMock).toHaveBeenCalled()
+      const callArgs = mockInput._promptMock.mock.calls[0][0]
+      expect(callArgs.body.agent).toBe("Atlas (Plan Executor)")
+      expect(callArgs.body.agent).not.toBe("atlas")
+    })
+
     test("should debounce rapid continuation injections (prevent infinite loop)", async () => {
       // given - boulder state with incomplete plan
       const planPath = join(TEST_DIR, "test-plan.md")

src/plugin-handlers/agent-key-remapper.test.ts

@@ -12,10 +12,10 @@ describe("remapAgentKeysToDisplayNames", () => {
     // when remapping
     const result = remapAgentKeysToDisplayNames(agents)
 
-    // then known agents get display name keys and config key aliases
+    // then known agents get display name keys only
     expect(result["Sisyphus (Ultraworker)"]).toBeDefined()
     expect(result["oracle"]).toBeDefined()
-    expect(result["sisyphus"]).toBeDefined()
+    expect(result["sisyphus"]).toBeUndefined()
   })
 
   it("preserves unknown agent keys unchanged", () => {
@@ -38,6 +38,7 @@ describe("remapAgentKeysToDisplayNames", () => {
       hephaestus: {},
       prometheus: {},
       atlas: {},
+      athena: {},
       metis: {},
       momus: {},
       "sisyphus-junior": {},
@@ -46,20 +47,37 @@ describe("remapAgentKeysToDisplayNames", () => {
     // when remapping
     const result = remapAgentKeysToDisplayNames(agents)
 
-    // then all get display name keys with config key aliases preserved
+    // then all get display name keys
     expect(result["Sisyphus (Ultraworker)"]).toBeDefined()
-    expect(result["sisyphus"]).toBeDefined()
+    expect(result["sisyphus"]).toBeUndefined()
     expect(result["Hephaestus (Deep Agent)"]).toBeDefined()
-    expect(result["hephaestus"]).toBeDefined()
+    expect(result["hephaestus"]).toBeUndefined()
     expect(result["Prometheus (Plan Builder)"]).toBeDefined()
-    expect(result["prometheus"]).toBeDefined()
+    expect(result["prometheus"]).toBeUndefined()
     expect(result["Atlas (Plan Executor)"]).toBeDefined()
-    expect(result["atlas"]).toBeDefined()
+    expect(result["atlas"]).toBeUndefined()
+    expect(result["Athena (Council)"]).toBeDefined()
+    expect(result["athena"]).toBeUndefined()
     expect(result["Metis (Plan Consultant)"]).toBeDefined()
-    expect(result["metis"]).toBeDefined()
+    expect(result["metis"]).toBeUndefined()
     expect(result["Momus (Plan Critic)"]).toBeDefined()
-    expect(result["momus"]).toBeDefined()
+    expect(result["momus"]).toBeUndefined()
     expect(result["Sisyphus-Junior"]).toBeDefined()
-    expect(result["sisyphus-junior"]).toBeDefined()
+    expect(result["sisyphus-junior"]).toBeUndefined()
+  })
+
+  it("does not emit both config and display keys for remapped agents", () => {
+    // given one remapped agent
+    const agents = {
+      sisyphus: { prompt: "test", mode: "primary" },
+    }
+
+    // when remapping
+    const result = remapAgentKeysToDisplayNames(agents)
+
+    // then only display key is emitted
+    expect(Object.keys(result)).toEqual(["Sisyphus (Ultraworker)"])
+    expect(result["Sisyphus (Ultraworker)"]).toBeDefined()
+    expect(result["sisyphus"]).toBeUndefined()
   })
 })

src/plugin-handlers/agent-key-remapper.ts

@@ -9,7 +9,11 @@ export function remapAgentKeysToDisplayNames(
     const displayName = AGENT_DISPLAY_NAMES[key]
     if (displayName && displayName !== key) {
       result[displayName] = value
-      result[key] = value
+      // Regression guard: do not also assign result[key].
+      // This line was repeatedly re-added and caused duplicate agent rows in the UI.
+      // Runtime callers that previously depended on config-key aliases were fixed in:
+      // - hooks/atlas/boulder-continuation-injector.ts (prompt agent normalization)
+      // - features/claude-code-session-state/state.ts (dual registration for display + config forms)
     } else {
       result[key] = value
     }

src/shared/agent-display-names.test.ts

@@ -187,10 +187,13 @@ describe("AGENT_DISPLAY_NAMES", () => {
       "sisyphus-junior": "Sisyphus-Junior",
       metis: "Metis (Plan Consultant)",
       momus: "Momus (Plan Critic)",
+      athena: "Athena (Council)",
+      "athena-junior": "Athena-Junior (Council)",
       oracle: "oracle",
       librarian: "librarian",
       explore: "explore",
       "multimodal-looker": "multimodal-looker",
+      "council-member": "council-member",
     }
 
     // when checking the constant

src/shared/agent-display-names.ts

@@ -11,10 +11,13 @@ export const AGENT_DISPLAY_NAMES: Record<string, string> = {
   "sisyphus-junior": "Sisyphus-Junior",
   metis: "Metis (Plan Consultant)",
   momus: "Momus (Plan Critic)",
+  athena: "Athena (Council)",
+  "athena-junior": "Athena-Junior (Council)",
   oracle: "oracle",
   librarian: "librarian",
   explore: "explore",
   "multimodal-looker": "multimodal-looker",
+  "council-member": "council-member",
 }
 
 /**
@@ -51,4 +54,32 @@ export function getAgentConfigKey(agentName: string): string {
   if (reversed !== undefined) return reversed
   if (AGENT_DISPLAY_NAMES[lower] !== undefined) return lower
   return lower
-}
+}
+
+/**
+ * Normalize an agent name for prompt APIs.
+ * - Known display names -> canonical display names
+ * - Known config keys (any case) -> canonical display names
+ * - Unknown/custom names -> preserved as-is (trimmed)
+ */
+export function normalizeAgentForPrompt(agentName: string | undefined): string | undefined {
+  if (typeof agentName !== "string") {
+    return undefined
+  }
+
+  const trimmed = agentName.trim()
+  if (!trimmed) {
+    return undefined
+  }
+
+  const lower = trimmed.toLowerCase()
+  const reversed = REVERSE_DISPLAY_NAMES[lower]
+  if (reversed !== undefined) {
+    return AGENT_DISPLAY_NAMES[reversed] ?? trimmed
+  }
+  if (AGENT_DISPLAY_NAMES[lower] !== undefined) {
+    return AGENT_DISPLAY_NAMES[lower]
+  }
+
+  return trimmed
+}