feat(plugin): include parent agent context in hook inputs

ArmirKS · ArmirKS · commit 24eb459f6e38 · 2026-04-10T22:27:49.000+02:00
diff --git a/packages/opencode/src/session/llm.ts b/packages/opencode/src/session/llm.ts
@@ -171,6 +171,7 @@ export namespace LLM {
       {
         sessionID: input.sessionID,
         agent: input.agent.name,
+        parentAgent: input.user.parentAgent,
         model: input.model,
         provider,
         message: input.user,
@@ -191,6 +192,7 @@ export namespace LLM {
       {
         sessionID: input.sessionID,
         agent: input.agent.name,
+        parentAgent: input.user.parentAgent,
         model: input.model,
         provider,
         message: input.user,
diff --git a/packages/opencode/src/session/message-v2.ts b/packages/opencode/src/session/message-v2.ts
@@ -368,6 +368,7 @@ export namespace MessageV2 {
       })
       .optional(),
     agent: z.string(),
+    parentAgent: z.string().optional(),
     model: z.object({
       providerID: ProviderID.zod,
       modelID: ModelID.zod,
diff --git a/packages/opencode/src/session/prompt.ts b/packages/opencode/src/session/prompt.ts
@@ -347,6 +347,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
         processor: Pick<SessionProcessor.Handle, "message" | "updateToolCall" | "completeToolCall">
         bypassAgentCheck: boolean
         messages: MessageV2.WithParts[]
+        parentAgent?: string
       }) {
         using _ = log.time("resolveTools")
         const tools: Record<string, AITool> = {}
@@ -402,7 +403,14 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                   const ctx = context(args, options)
                   yield* plugin.trigger(
                     "tool.execute.before",
-                    { tool: item.id, sessionID: ctx.sessionID, callID: ctx.callID },
+                    {
+                      tool: item.id,
+                      sessionID: ctx.sessionID,
+                      messageID: input.processor.message.id,
+                      callID: ctx.callID,
+                      agent: ctx.agent,
+                      parentAgent: input.parentAgent,
+                    },
                     { args },
                   )
                   const result = yield* Effect.promise(() => item.execute(args, ctx))
@@ -417,7 +425,15 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                   }
                   yield* plugin.trigger(
                     "tool.execute.after",
-                    { tool: item.id, sessionID: ctx.sessionID, callID: ctx.callID, args },
+                    {
+                      tool: item.id,
+                      sessionID: ctx.sessionID,
+                      messageID: input.processor.message.id,
+                      callID: ctx.callID,
+                      args,
+                      agent: ctx.agent,
+                      parentAgent: input.parentAgent,
+                    },
                     output,
                   )
                   if (options.abortSignal?.aborted) {
@@ -443,7 +459,14 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                 const ctx = context(args, opts)
                 yield* plugin.trigger(
                   "tool.execute.before",
-                  { tool: key, sessionID: ctx.sessionID, callID: opts.toolCallId },
+                  {
+                    tool: key,
+                    sessionID: ctx.sessionID,
+                    messageID: input.processor.message.id,
+                    callID: opts.toolCallId,
+                    agent: ctx.agent,
+                    parentAgent: input.parentAgent,
+                  },
                   { args },
                 )
                 yield* Effect.promise(() => ctx.ask({ permission: key, metadata: {}, patterns: ["*"], always: ["*"] }))
@@ -452,7 +475,15 @@ NOTE: At any point in time through this workflow you should feel free to ask the
                 )
                 yield* plugin.trigger(
                   "tool.execute.after",
-                  { tool: key, sessionID: ctx.sessionID, callID: opts.toolCallId, args },
+                  {
+                    tool: key,
+                    sessionID: ctx.sessionID,
+                    messageID: input.processor.message.id,
+                    callID: opts.toolCallId,
+                    args,
+                    agent: ctx.agent,
+                    parentAgent: input.parentAgent,
+                  },
                   result,
                 )
 
@@ -564,7 +595,14 @@ NOTE: At any point in time through this workflow you should feel free to ask the
         }
         yield* plugin.trigger(
           "tool.execute.before",
-          { tool: TaskTool.id, sessionID, callID: part.id },
+          {
+            tool: TaskTool.id,
+            sessionID,
+            messageID: assistantMessage.id,
+            callID: part.id,
+            agent: lastUser.agent,
+            parentAgent: lastUser.parentAgent,
+          },
           { args: taskArgs },
         )
 
@@ -582,6 +620,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
           taskTool
             .execute(taskArgs, {
               agent: task.agent,
+              parentAgent: lastUser.agent,
               messageID: assistantMessage.id,
               sessionID,
               abort: signal,
@@ -645,7 +684,15 @@ NOTE: At any point in time through this workflow you should feel free to ask the
 
         yield* plugin.trigger(
           "tool.execute.after",
-          { tool: TaskTool.id, sessionID, callID: part.id, args: taskArgs },
+          {
+            tool: TaskTool.id,
+            sessionID,
+            messageID: assistantMessage.id,
+            callID: part.id,
+            args: taskArgs,
+            agent: lastUser.agent,
+            parentAgent: lastUser.parentAgent,
+          },
           result,
         )
 
@@ -726,6 +773,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
           time: { created: Date.now() },
           role: "user",
           agent: input.agent,
+          parentAgent: input.parentAgent,
           model: { providerID: model.providerID, modelID: model.modelID },
         }
         yield* sessions.updateMessage(userMsg)
@@ -812,7 +860,14 @@ NOTE: At any point in time through this workflow you should feel free to ask the
         const cwd = ctx.directory
         const shellEnv = yield* plugin.trigger(
           "shell.env",
-          { cwd, sessionID: input.sessionID, callID: part.callID },
+          {
+            cwd,
+            sessionID: input.sessionID,
+            messageID: part.messageID,
+            callID: part.callID,
+            agent: input.agent,
+            parentAgent: input.parentAgent,
+          },
           { env: {} },
         )
 
@@ -1702,6 +1757,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
       })
       .optional(),
     agent: z.string().optional(),
+    parentAgent: z.string().optional(),
     noReply: z.boolean().optional(),
     tools: z
       .record(z.string(), z.boolean())
@@ -1783,6 +1839,7 @@ NOTE: At any point in time through this workflow you should feel free to ask the
     sessionID: SessionID.zod,
     messageID: MessageID.zod.optional(),
     agent: z.string(),
+    parentAgent: z.string().optional(),
     model: z
       .object({
         providerID: ProviderID.zod,
diff --git a/packages/opencode/src/tool/bash.ts b/packages/opencode/src/tool/bash.ts
@@ -364,7 +364,14 @@ export const BashTool = Tool.defineEffect(
     const shellEnv = Effect.fn("BashTool.shellEnv")(function* (ctx: Tool.Context, cwd: string) {
       const extra = yield* plugin.trigger(
         "shell.env",
-        { cwd, sessionID: ctx.sessionID, callID: ctx.callID },
+        {
+          cwd,
+          sessionID: ctx.sessionID,
+          messageID: ctx.messageID,
+          callID: ctx.callID,
+          agent: ctx.agent,
+          parentAgent: ctx.parentAgent,
+        },
         { env: {} },
       )
       return {
diff --git a/packages/opencode/src/tool/task.ts b/packages/opencode/src/tool/task.ts
@@ -135,6 +135,7 @@ export const TaskTool = Tool.defineEffect(
                   providerID: model.providerID,
                 },
                 agent: next.name,
+                parentAgent: ctx.agent,
                 tools: {
                   ...(canTodo ? {} : { todowrite: false }),
                   ...(canTask ? {} : { task: false }),
diff --git a/packages/opencode/src/tool/tool.ts b/packages/opencode/src/tool/tool.ts
@@ -18,6 +18,7 @@ export namespace Tool {
     sessionID: SessionID
     messageID: MessageID
     agent: string
+    parentAgent?: string
     abort: AbortSignal
     callID?: string
     extra?: { [key: string]: any }
diff --git a/packages/opencode/test/plugin/parent-agent.test.ts b/packages/opencode/test/plugin/parent-agent.test.ts
@@ -0,0 +1,63 @@
+import { describe, expect, test } from "bun:test"
+import { SessionPrompt } from "../../src/session/prompt"
+import { MessageV2 } from "../../src/session/message-v2"
+import { Identifier } from "../../src/id/id"
+
+const SESSION_ID = Identifier.descending("session")
+const MESSAGE_ID = Identifier.ascending("message")
+
+describe("parentAgent hook input", () => {
+  test("PromptInput accepts parentAgent", () => {
+    const input = SessionPrompt.PromptInput.parse({
+      sessionID: SESSION_ID,
+      agent: "scout",
+      parentAgent: "coder",
+      parts: [{ type: "text", text: "test" }],
+    })
+    expect(input.parentAgent).toBe("coder")
+  })
+
+  test("PromptInput parentAgent is optional", () => {
+    const input = SessionPrompt.PromptInput.parse({
+      sessionID: SESSION_ID,
+      agent: "scout",
+      parts: [{ type: "text", text: "test" }],
+    })
+    expect(input.parentAgent).toBeUndefined()
+  })
+
+  test("ShellInput accepts parentAgent", () => {
+    const input = SessionPrompt.ShellInput.parse({
+      sessionID: SESSION_ID,
+      agent: "coder",
+      parentAgent: "orchestrator",
+      command: "ls",
+    })
+    expect(input.parentAgent).toBe("orchestrator")
+  })
+
+  test("UserMessage stores parentAgent", () => {
+    const msg = MessageV2.User.parse({
+      id: MESSAGE_ID,
+      sessionID: SESSION_ID,
+      role: "user",
+      time: { created: Date.now() },
+      agent: "scout",
+      parentAgent: "coder",
+      model: { providerID: "anthropic", modelID: "claude-sonnet-4-6" },
+    })
+    expect(msg.parentAgent).toBe("coder")
+  })
+
+  test("UserMessage parentAgent is optional", () => {
+    const msg = MessageV2.User.parse({
+      id: MESSAGE_ID,
+      sessionID: SESSION_ID,
+      role: "user",
+      time: { created: Date.now() },
+      agent: "coder",
+      model: { providerID: "openai", modelID: "gpt-5.4" },
+    })
+    expect(msg.parentAgent).toBeUndefined()
+  })
+})
diff --git a/packages/plugin/src/index.ts b/packages/plugin/src/index.ts
@@ -211,7 +211,14 @@ export interface Hooks {
    * Modify parameters sent to LLM
    */
   "chat.params"?: (
-    input: { sessionID: string; agent: string; model: Model; provider: ProviderContext; message: UserMessage },
+    input: {
+      sessionID: string
+      agent: string
+      parentAgent?: string
+      model: Model
+      provider: ProviderContext
+      message: UserMessage
+    },
     output: {
       temperature: number
       topP: number
@@ -221,7 +228,14 @@ export interface Hooks {
     },
   ) => Promise<void>
   "chat.headers"?: (
-    input: { sessionID: string; agent: string; model: Model; provider: ProviderContext; message: UserMessage },
+    input: {
+      sessionID: string
+      agent: string
+      parentAgent?: string
+      model: Model
+      provider: ProviderContext
+      message: UserMessage
+    },
     output: { headers: Record<string, string> },
   ) => Promise<void>
   "permission.ask"?: (input: Permission, output: { status: "ask" | "deny" | "allow" }) => Promise<void>
@@ -230,15 +244,30 @@ export interface Hooks {
     output: { parts: Part[] },
   ) => Promise<void>
   "tool.execute.before"?: (
-    input: { tool: string; sessionID: string; callID: string },
+    input: { tool: string; sessionID: string; messageID: string; callID: string; agent?: string; parentAgent?: string },
     output: { args: any },
   ) => Promise<void>
   "shell.env"?: (
-    input: { cwd: string; sessionID?: string; callID?: string },
+    input: {
+      cwd: string
+      sessionID?: string
+      messageID?: string
+      callID?: string
+      agent?: string
+      parentAgent?: string
+    },
     output: { env: Record<string, string> },
   ) => Promise<void>
   "tool.execute.after"?: (
-    input: { tool: string; sessionID: string; callID: string; args: any },
+    input: {
+      tool: string
+      sessionID: string
+      messageID: string
+      callID: string
+      args: any
+      agent?: string
+      parentAgent?: string
+    },
     output: {
       title: string
       output: string
