fix(prometheus): prevent agent fallback to build in background tasks (#695)

src/tools/background-task/tools.ts

@@ -4,7 +4,9 @@ import { join } from "node:path"
 import type { BackgroundManager, BackgroundTask } from "../../features/background-agent"
 import type { BackgroundTaskArgs, BackgroundOutputArgs, BackgroundCancelArgs } from "./types"
 import { BACKGROUND_TASK_DESCRIPTION, BACKGROUND_OUTPUT_DESCRIPTION, BACKGROUND_CANCEL_DESCRIPTION } from "./constants"
-import { findNearestMessageWithFields, MESSAGE_STORAGE } from "../../features/hook-message-injector"
+import { findNearestMessageWithFields, findFirstMessageWithAgent, MESSAGE_STORAGE } from "../../features/hook-message-injector"
+import { getSessionAgent } from "../../features/claude-code-session-state"
+import { log } from "../../shared/logger"
 
 type OpencodeClient = PluginInput["client"]
 
@@ -63,6 +65,19 @@ export function createBackgroundTask(manager: BackgroundManager): ToolDefinition
       try {
         const messageDir = getMessageDir(ctx.sessionID)
         const prevMessage = messageDir ? findNearestMessageWithFields(messageDir) : null
+        const firstMessageAgent = messageDir ? findFirstMessageWithAgent(messageDir) : null
+        const sessionAgent = getSessionAgent(ctx.sessionID)
+        const parentAgent = ctx.agent ?? sessionAgent ?? firstMessageAgent ?? prevMessage?.agent
+        
+        log("[background_task] parentAgent resolution", {
+          sessionID: ctx.sessionID,
+          ctxAgent: ctx.agent,
+          sessionAgent,
+          firstMessageAgent,
+          prevMessageAgent: prevMessage?.agent,
+          resolvedParentAgent: parentAgent,
+        })
+        
         const parentModel = prevMessage?.model?.providerID && prevMessage?.model?.modelID
           ? { providerID: prevMessage.model.providerID, modelID: prevMessage.model.modelID }
           : undefined
@@ -74,7 +89,7 @@ export function createBackgroundTask(manager: BackgroundManager): ToolDefinition
           parentSessionID: ctx.sessionID,
           parentMessageID: ctx.messageID,
           parentModel,
-          parentAgent: ctx.agent ?? prevMessage?.agent,
+          parentAgent,
         })
 
         ctx.metadata?.({

src/tools/call-omo-agent/tools.ts

@@ -1,8 +1,26 @@
 import { tool, type PluginInput, type ToolDefinition } from "@opencode-ai/plugin"
+import { existsSync, readdirSync } from "node:fs"
+import { join } from "node:path"
 import { ALLOWED_AGENTS, CALL_OMO_AGENT_DESCRIPTION } from "./constants"
 import type { CallOmoAgentArgs } from "./types"
 import type { BackgroundManager } from "../../features/background-agent"
 import { log } from "../../shared/logger"
+import { findFirstMessageWithAgent, findNearestMessageWithFields, MESSAGE_STORAGE } from "../../features/hook-message-injector"
+import { getSessionAgent } from "../../features/claude-code-session-state"
+
+function getMessageDir(sessionID: string): string | null {
+  if (!existsSync(MESSAGE_STORAGE)) return null
+
+  const directPath = join(MESSAGE_STORAGE, sessionID)
+  if (existsSync(directPath)) return directPath
+
+  for (const dir of readdirSync(MESSAGE_STORAGE)) {
+    const sessionPath = join(MESSAGE_STORAGE, dir, sessionID)
+    if (existsSync(sessionPath)) return sessionPath
+  }
+
+  return null
+}
 
 type ToolContextWithMetadata = {
   sessionID: string
@@ -60,12 +78,29 @@ async function executeBackground(
   manager: BackgroundManager
 ): Promise<string> {
   try {
+    const messageDir = getMessageDir(toolContext.sessionID)
+    const prevMessage = messageDir ? findNearestMessageWithFields(messageDir) : null
+    const firstMessageAgent = messageDir ? findFirstMessageWithAgent(messageDir) : null
+    const sessionAgent = getSessionAgent(toolContext.sessionID)
+    const parentAgent = toolContext.agent ?? sessionAgent ?? firstMessageAgent ?? prevMessage?.agent
+    
+    log("[call_omo_agent] parentAgent resolution", {
+      sessionID: toolContext.sessionID,
+      messageDir,
+      ctxAgent: toolContext.agent,
+      sessionAgent,
+      firstMessageAgent,
+      prevMessageAgent: prevMessage?.agent,
+      resolvedParentAgent: parentAgent,
+    })
+
     const task = await manager.launch({
       description: args.description,
       prompt: args.prompt,
       agent: args.subagent_type,
       parentSessionID: toolContext.sessionID,
       parentMessageID: toolContext.messageID,
+      parentAgent,
     })
 
     toolContext.metadata?.({

src/tools/sisyphus-task/tools.ts

@@ -5,11 +5,12 @@ import type { BackgroundManager } from "../../features/background-agent"
 import type { SisyphusTaskArgs } from "./types"
 import type { CategoryConfig, CategoriesConfig, GitMasterConfig } from "../../config/schema"
 import { SISYPHUS_TASK_DESCRIPTION, DEFAULT_CATEGORIES, CATEGORY_PROMPT_APPENDS } from "./constants"
-import { findNearestMessageWithFields, MESSAGE_STORAGE } from "../../features/hook-message-injector"
+import { findNearestMessageWithFields, findFirstMessageWithAgent, MESSAGE_STORAGE } from "../../features/hook-message-injector"
 import { resolveMultipleSkills } from "../../features/opencode-skill-loader/skill-content"
 import { createBuiltinSkills } from "../../features/builtin-skills/skills"
 import { getTaskToastManager } from "../../features/task-toast-manager"
-import { subagentSessions } from "../../features/claude-code-session-state"
+import { subagentSessions, getSessionAgent } from "../../features/claude-code-session-state"
+import { log } from "../../shared/logger"
 
 type OpencodeClient = PluginInput["client"]
 
@@ -147,7 +148,19 @@ export function createSisyphusTask(options: SisyphusTaskToolOptions): ToolDefini
 
       const messageDir = getMessageDir(ctx.sessionID)
       const prevMessage = messageDir ? findNearestMessageWithFields(messageDir) : null
-      const parentAgent = ctx.agent ?? prevMessage?.agent
+      const firstMessageAgent = messageDir ? findFirstMessageWithAgent(messageDir) : null
+      const sessionAgent = getSessionAgent(ctx.sessionID)
+      const parentAgent = ctx.agent ?? sessionAgent ?? firstMessageAgent ?? prevMessage?.agent
+      
+      log("[sisyphus_task] parentAgent resolution", {
+        sessionID: ctx.sessionID,
+        messageDir,
+        ctxAgent: ctx.agent,
+        sessionAgent,
+        firstMessageAgent,
+        prevMessageAgent: prevMessage?.agent,
+        resolvedParentAgent: parentAgent,
+      })
       const parentModel = prevMessage?.model?.providerID && prevMessage?.model?.modelID
         ? { providerID: prevMessage.model.providerID, modelID: prevMessage.model.modelID }
         : undefined