feat(plugin): add session title hook and request options bag (#47663)

Author: rekram1-node

packages/core/src/session/compaction.ts

@@ -11,7 +11,6 @@ import {
   Message,
   type ContentPart,
 } from "@opencode/ai"
-import { Agent } from "@opencode/schema/agent"
 import { SessionError } from "@opencode/schema/session-error"
 import { Context, Effect, Layer, Stream } from "effect"
 import { Bus } from "../bus.js"
@@ -97,7 +96,7 @@ export type Editor = {
 
 export type AutoInput = {
   readonly context: SessionContext.Loaded
-  readonly prepare: SessionModelRequest.Interface["prepare"]
+  readonly prepare: SessionModelRequest.Interface["compaction"]
   /** Known overflow must recover from durable history, not submit the overflowing native window again. */
   readonly overflow?: boolean
 }
@@ -120,7 +119,7 @@ export type ManualInput = {
     SessionContext.Loaded & { readonly instructionUpdate: string },
     SessionRunnerModel.Error | AgentNotFoundError | Instructions.InitializationBlocked
   >
-  readonly prepare: SessionModelRequest.Interface["prepare"]
+  readonly prepare: SessionModelRequest.Interface["compaction"]
 }
 
 type ExecuteInput = AutoInput & {
@@ -428,22 +427,16 @@ export const layer = Layer.effect(
         messages,
       })
       return input.prepare({
-        kind: "compaction",
-        scope: {
-          session: context.session,
-          agentID: Agent.ID.make("compaction"),
-          contextAgentID: context.agent.id,
-          model: context.model,
-          tools: context.tools,
-        },
-        transcript: {
-          system: transcript.system,
-          messages: [
-            ...transcript.messages,
-            ...(input.instructionUpdate ? [Message.system(input.instructionUpdate)] : []),
-            ...prompt,
-          ],
-        },
+        session: context.session,
+        agent: context.agent.id,
+        model: context.model,
+        tools: context.tools,
+        system: transcript.system,
+        messages: [
+          ...transcript.messages,
+          ...(input.instructionUpdate ? [Message.system(input.instructionUpdate)] : []),
+          ...prompt,
+        ],
         webSocket,
       })
     }
@@ -478,7 +471,7 @@ export const layer = Layer.effect(
           "Provider compaction requires the endpoint in provider/model settings, not a model.request rewrite",
         )
       const transient = SessionRunnerRetry.transient(yield* SessionRunnerRetry.policy(context.session.id), {
-        agent: Agent.ID.make("compaction"),
+        agent: context.agent.id,
         model: context.model.ref,
         hook: prepared.retry,
       })
@@ -580,7 +573,7 @@ export const layer = Layer.effect(
       ])
       // Both requests share the retry allowance; rejected output never enters the reminder request.
       const transient = SessionRunnerRetry.transient(yield* SessionRunnerRetry.policy(context.session.id), {
-        agent: Agent.ID.make("compaction"),
+        agent: context.agent.id,
         model: context.model.ref,
         hook: prepared.retry,
       })

packages/core/src/session/context.ts

@@ -65,7 +65,7 @@ export interface Interface {
       }
     | undefined
   >
-  readonly prepare: SessionModelRequest.Interface["prepare"]
+  readonly request: SessionModelRequest.Interface
 }
 
 /** Location-scoped model-context loader for durable Session Steps. */
@@ -84,7 +84,7 @@ const layer = Layer.effect(
     const mcpInstructions = yield* McpInstructions.Service
     const mcpTools = yield* McpTool.Service
     const models = yield* SessionRunnerModel.Service
-    const modelRequests = yield* SessionModelRequest.Service
+    const request = yield* SessionModelRequest.Service
     const referenceInstructions = yield* ReferenceInstructions.Service
     const skillInstructions = yield* SkillInstructions.Service
     const store = yield* SessionStore.Service
@@ -173,7 +173,7 @@ const layer = Layer.effect(
       }
     })
 
-    return Service.of({ select, load, resolveModel, selectTitle, prepare: modelRequests.prepare })
+    return Service.of({ select, load, resolveModel, selectTitle, request })
   }),
 )
 

packages/core/src/session/generate.ts

@@ -43,17 +43,17 @@ export const generate = Effect.fn("SessionGenerate.generate")(function* (input:
       initial: history.initial,
       messages: history.messages,
     })
-    const prepared = yield* context.prepare({
-      kind: "generate",
-      scope: { session: selection.session, agentID: selection.agent.id, model, tools: selection.tools },
-      transcript: {
-        system: transcript.system,
-        messages: [
-          ...transcript.messages,
-          ...(history.instructionUpdate ? [Message.system(history.instructionUpdate)] : []),
-          Message.user(input.prompt),
-        ],
-      },
+    const prepared = yield* context.request.generate({
+      session: selection.session,
+      agent: selection.agent.id,
+      model,
+      tools: selection.tools,
+      system: transcript.system,
+      messages: [
+        ...transcript.messages,
+        ...(history.instructionUpdate ? [Message.system(history.instructionUpdate)] : []),
+        Message.user(input.prompt),
+      ],
     })
     yield* Effect.logInfo("sending session generation request", {
       sessionID: selection.session.id,