fix(core): retain raw copilot completion usage

packages/app/src/components/prompt-input/submit.ts

@@ -76,27 +76,6 @@ export async function sendFollowupDraft(input: FollowupSendInput) {
     return true
   }
 
-  const select = async () => {
-    const session = input.session()
-    if (session?.agent !== input.draft.agent) {
-      await input.api.switchAgent({ sessionID: input.draft.sessionID, agent: input.draft.agent })
-    }
-    if (
-      session?.model?.providerID === input.draft.model.providerID &&
-      session.model.id === input.draft.model.modelID &&
-      (session.model.variant ?? "default") === (input.draft.variant ?? "default")
-    )
-      return
-    await input.api.switchModel({
-      sessionID: input.draft.sessionID,
-      model: {
-        id: input.draft.model.modelID,
-        providerID: input.draft.model.providerID,
-        variant: input.draft.variant,
-      },
-    })
-  }
-
   const [head, ...tail] = text.split(" ")
   const cmd = head?.startsWith("/") ? head.slice(1) : undefined
   if (cmd && input.sync.data.command.find((item) => item.name === cmd)) {
@@ -107,13 +86,18 @@ export async function sendFollowupDraft(input: FollowupSendInput) {
         return false
       }
 
-      await select()
       const messageID = Identifier.ascending("message")
       await input.api.command({
         sessionID: input.draft.sessionID,
         id: messageID,
         command: cmd,
         arguments: tail.join(" "),
+        agent: input.draft.agent,
+        model: {
+          id: input.draft.model.modelID,
+          providerID: input.draft.model.providerID,
+          variant: input.draft.variant,
+        },
         files: await Promise.all(
           images.map(async (attachment) => ({
             uri: await blobDataUrl(attachment.blob, attachment.mime),
@@ -183,7 +167,24 @@ export async function sendFollowupDraft(input: FollowupSendInput) {
       return false
     }
 
-    await select()
+    const session = input.session()
+    if (session?.agent !== input.draft.agent) {
+      await input.api.switchAgent({ sessionID: input.draft.sessionID, agent: input.draft.agent })
+    }
+    if (
+      session?.model?.providerID !== input.draft.model.providerID ||
+      session.model.id !== input.draft.model.modelID ||
+      (session.model.variant ?? "default") !== (input.draft.variant ?? "default")
+    ) {
+      await input.api.switchModel({
+        sessionID: input.draft.sessionID,
+        model: {
+          id: input.draft.model.modelID,
+          providerID: input.draft.model.providerID,
+          variant: input.draft.variant,
+        },
+      })
+    }
 
     await input.api.prompt({
       sessionID: input.draft.sessionID,
@@ -523,22 +524,14 @@ export function createPromptSubmit(input: PromptSubmitInput) {
         clearInput()
         const messageID = Identifier.ascending("message")
         serverSync().session.set("session_status", session.id, { type: "busy" })
-        void (async () => {
-          if (session.agent !== agent) await sdk().api.session.switchAgent({ sessionID: session.id, agent })
-          if (
-            session.model?.providerID !== model.providerID ||
-            session.model.id !== model.modelID ||
-            (session.model.variant ?? "default") !== (variant ?? "default")
-          )
-            await sdk().api.session.switchModel({
-              sessionID: session.id,
-              model: { id: model.modelID, providerID: model.providerID, variant },
-            })
-          await sdk().api.session.command({
+        sdk()
+          .api.session.command({
             sessionID: session.id,
             id: messageID,
             command: commandName,
             arguments: args.join(" "),
+            agent,
+            model: { id: model.modelID, providerID: model.providerID, variant },
             files: await Promise.all(
               images.map(async (attachment) => ({
                 uri: await blobDataUrl(attachment.blob, attachment.mime),
@@ -546,14 +539,14 @@ export function createPromptSubmit(input: PromptSubmitInput) {
               })),
             ),
           })
-        })().catch((err) => {
-          serverSync().session.set("session_status", session.id, { type: "idle" })
-          showToast({
-            title: language.t("prompt.toast.commandSendFailed.title"),
-            description: formatServerError(err, language.t, language.t("common.requestFailed")),
+          .catch((err) => {
+            serverSync().session.set("session_status", session.id, { type: "idle" })
+            showToast({
+              title: language.t("prompt.toast.commandSendFailed.title"),
+              description: formatServerError(err, language.t, language.t("common.requestFailed")),
+            })
+            restoreInput()
           })
-          restoreInput()
-        })
         return
       }
     }

packages/client/src/effect/api/api.ts

@@ -193,6 +193,8 @@ export type Endpoint5_13Input = {
   readonly id?: SessionMessage.ID | undefined
   readonly command: string
   readonly arguments?: string | undefined
+  readonly agent?: Agent.ID | undefined
+  readonly model?: Model.Ref | undefined
   readonly files?: ReadonlyArray<PromptInput.FileAttachment> | undefined
   readonly agents?: ReadonlyArray<AgentAttachment> | undefined
   readonly skills?: ReadonlyArray<PromptInput.SkillAttachment> | undefined

packages/client/src/effect/generated/client.ts

@@ -431,6 +431,8 @@ const Endpoint5_13 = (raw: RawClient["server.session"]) => (input: Endpoint5_13I
         id: input["id"],
         command: input["command"],
         arguments: input["arguments"],
+        agent: input["agent"],
+        model: input["model"],
         files: input["files"],
         agents: input["agents"],
         skills: input["skills"],

packages/client/src/promise/generated/client.ts

@@ -635,6 +635,8 @@ export function make(options: ClientOptions) {
               id: input["id"],
               command: input["command"],
               arguments: input["arguments"],
+              agent: input["agent"],
+              model: input["model"],
               files: input["files"],
               agents: input["agents"],
               skills: input["skills"],

packages/client/src/promise/generated/types.ts

@@ -41,6 +41,7 @@ export type SessionMessageAgentSelected = {
   time: { created: number }
   type: "agent-switched"
   agent: string
+  previous?: string
 }
 
 export type PromptBase64 = string
@@ -2535,6 +2536,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "agent-switched"
           readonly agent: string
+          readonly previous?: string
         }
       | {
           readonly id: string
@@ -2786,6 +2788,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "agent-switched"
           readonly agent: string
+          readonly previous?: string
         }
       | {
           readonly id: string
@@ -3037,6 +3040,7 @@ export type SessionImportInput = {
           readonly time: { readonly created: number }
           readonly type: "agent-switched"
           readonly agent: string
+          readonly previous?: string
         }
       | {
           readonly id: string
@@ -3485,6 +3489,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3506,6 +3512,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3527,6 +3535,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3544,10 +3554,58 @@ export type SessionCommandInput = {
     readonly delivery?: "steer" | "queue" | null
     readonly resume?: boolean | null
   }["arguments"]
+  readonly agent?: {
+    readonly id?: string | null
+    readonly command: string
+    readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
+    readonly files?: ReadonlyArray<{
+      readonly uri: string
+      readonly name?: string
+      readonly description?: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly agents?: ReadonlyArray<{
+      readonly name: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly skills?: ReadonlyArray<{
+      readonly id: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly delivery?: "steer" | "queue" | null
+    readonly resume?: boolean | null
+  }["agent"]
+  readonly model?: {
+    readonly id?: string | null
+    readonly command: string
+    readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
+    readonly files?: ReadonlyArray<{
+      readonly uri: string
+      readonly name?: string
+      readonly description?: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly agents?: ReadonlyArray<{
+      readonly name: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly skills?: ReadonlyArray<{
+      readonly id: string
+      readonly mention?: { readonly start: number; readonly end: number; readonly text: string }
+    }>
+    readonly delivery?: "steer" | "queue" | null
+    readonly resume?: boolean | null
+  }["model"]
   readonly files?: {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3569,6 +3627,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3590,6 +3650,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3611,6 +3673,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string
@@ -3632,6 +3696,8 @@ export type SessionCommandInput = {
     readonly id?: string | null
     readonly command: string
     readonly arguments?: string | null
+    readonly agent?: string | null
+    readonly model?: { readonly id: string; readonly providerID: string; readonly variant?: string } | null
     readonly files?: ReadonlyArray<{
       readonly uri: string
       readonly name?: string

packages/core/src/github-copilot/chat/openai-compatible-chat-language-model.ts

@@ -285,9 +285,8 @@ export class OpenAICompatibleChatLanguageModel implements LanguageModelV3 {
           cacheWrite: undefined,
         },
         outputTokens: {
-          total: responseBody.usage?.completion_tokens ?? undefined,
+          ...outputUsage(responseBody.usage),
           text: undefined,
-          reasoning: responseBody.usage?.completion_tokens_details?.reasoning_tokens ?? undefined,
         },
         raw: responseBody.usage ?? undefined,
       },
@@ -357,6 +356,7 @@ export class OpenAICompatibleChatLanguageModel implements LanguageModelV3 {
         cachedTokens: number | undefined
       }
       totalTokens: number | undefined
+      rawCompletionTokens: number | undefined
     } = {
       completionTokens: undefined,
       completionTokensDetails: {
@@ -369,6 +369,7 @@ export class OpenAICompatibleChatLanguageModel implements LanguageModelV3 {
         cachedTokens: undefined,
       },
       totalTokens: undefined,
+      rawCompletionTokens: undefined,
     }
     let isFirstChunk = true
     const providerOptionsName = this.providerOptionsName
@@ -432,11 +433,11 @@ export class OpenAICompatibleChatLanguageModel implements LanguageModelV3 {
               } = value.usage
 
               usage.promptTokens = prompt_tokens ?? undefined
-              usage.completionTokens = completion_tokens ?? undefined
+              usage.rawCompletionTokens = completion_tokens ?? undefined
+              const output = outputUsage(value.usage)
+              usage.completionTokens = output.total
+              usage.completionTokensDetails.reasoningTokens = output.reasoning
               usage.totalTokens = total_tokens ?? undefined
-              if (completion_tokens_details?.reasoning_tokens != null) {
-                usage.completionTokensDetails.reasoningTokens = completion_tokens_details?.reasoning_tokens
-              }
               if (completion_tokens_details?.accepted_prediction_tokens != null) {
                 usage.completionTokensDetails.acceptedPredictionTokens =
                   completion_tokens_details?.accepted_prediction_tokens
@@ -708,7 +709,7 @@ export class OpenAICompatibleChatLanguageModel implements LanguageModelV3 {
                 },
                 raw: {
                   prompt_tokens: usage.promptTokens ?? null,
-                  completion_tokens: usage.completionTokens ?? null,
+                  completion_tokens: usage.rawCompletionTokens ?? null,
                   total_tokens: usage.totalTokens ?? null,
                 },
               },
@@ -727,6 +728,7 @@ const openaiCompatibleTokenUsageSchema = z
   .object({
     prompt_tokens: z.number().nullish(),
     completion_tokens: z.number().nullish(),
+    reasoning_tokens: z.number().nullish(),
     total_tokens: z.number().nullish(),
     prompt_tokens_details: z
       .object({
@@ -743,6 +745,17 @@ const openaiCompatibleTokenUsageSchema = z
   })
   .nullish()
 
+function outputUsage(usage: z.infer<typeof openaiCompatibleTokenUsageSchema>) {
+  const nested = usage?.completion_tokens_details?.reasoning_tokens
+  return {
+    total:
+      usage?.completion_tokens == null
+        ? undefined
+        : usage.completion_tokens + (nested == null ? (usage.reasoning_tokens ?? 0) : 0),
+    reasoning: nested ?? usage?.reasoning_tokens ?? undefined,
+  }
+}
+
 // limited version of the schema, focussed on what is needed for the implementation
 // this approach limits breakages when the API changes and increases efficiency
 const OpenAICompatibleChatResponseSchema = z.object({

packages/core/src/plugin/promise.ts

@@ -310,6 +310,8 @@ export function fromPromise(plugin: Plugin) {
                   ...input,
                   sessionID: Session.ID.make(input.sessionID),
                   id: input.id == null ? undefined : SessionMessage.ID.make(input.id),
+                  agent: input.agent == null ? undefined : Agent.ID.make(input.agent),
+                  model: input.model == null ? undefined : model(input.model),
                   skills: input.skills?.map((skill) => ({ ...skill, id: Skill.ID.make(skill.id) })),
                   arguments: input.arguments ?? undefined,
                   delivery: input.delivery ?? undefined,

packages/core/src/session.ts

@@ -233,6 +233,8 @@ export interface Interface {
     sessionID: SessionSchema.ID
     command: string
     arguments?: string
+    agent?: Agent.ID
+    model?: Model.Ref
     files?: PromptInput.Prompt["files"]
     agents?: PromptInput.Prompt["agents"]
     skills?: PromptInput.Prompt["skills"]
@@ -623,13 +625,13 @@ const layer = Layer.effect(
         const evaluated = yield* commands.evaluate({ name: input.command, arguments: input.arguments })
 
         // TODO(v2 commands): decide whether command-level subtask/background execution belongs in v2 commands.
-        const agent = command.agent
+        const agent = command.agent ?? input.agent
         const commandAgent = yield* Effect.gen(function* () {
           if (!command.agent) return undefined
           const agents = yield* Agent.Service.pipe(Effect.provide(locations.get(session.location)))
           return yield* agents.get(Agent.ID.make(command.agent))
         })
-        const model = command.model ?? commandAgent?.model
+        const model = command.model ?? commandAgent?.model ?? input.model
         if (agent !== undefined && session.agent !== Agent.ID.make(agent))
           yield* result.switchAgent({ sessionID: input.sessionID, agent: Agent.ID.make(agent) })
         if (model !== undefined) yield* result.switchModel({ sessionID: input.sessionID, model })

packages/core/src/session/message-updater.ts

@@ -4,6 +4,7 @@ import { SessionEvent } from "./event"
 import { SessionMessage } from "./message"
 
 export interface Adapter {
+  readonly getAgent: () => Effect.Effect<SessionMessage.AgentSelected["agent"] | undefined, never, never>
   readonly getModel: () => Effect.Effect<SessionMessage.ModelSelected["model"] | undefined, never, never>
   readonly getCurrentAssistant: () => Effect.Effect<SessionMessage.Assistant | undefined, never, never>
   readonly getAssistant: (
@@ -59,15 +60,19 @@ export function update(adapter: Adapter, event: SessionEvent.DurableEvent) {
       "session.created": () => Effect.void,
       "session.usage.recorded": () => Effect.void,
       "session.agent.selected": (event) => {
-        return adapter.appendMessage(
-          SessionMessage.AgentSelected.make({
-            id: SessionMessage.ID.fromEvent(event.id),
-            type: "agent-switched",
-            metadata: event.metadata,
-            agent: event.data.agent,
-            time: { created: event.created },
-          }),
-        )
+        return Effect.gen(function* () {
+          const previous = yield* adapter.getAgent()
+          yield* adapter.appendMessage(
+            SessionMessage.AgentSelected.make({
+              id: SessionMessage.ID.fromEvent(event.id),
+              type: "agent-switched",
+              metadata: event.metadata,
+              agent: event.data.agent,
+              previous,
+              time: { created: event.created },
+            }),
+          )
+        })
       },
       "session.model.selected": (event) => {
         return Effect.gen(function* () {

packages/core/src/session/projector.ts

@@ -5,6 +5,7 @@ import { DateTime, Effect, Layer, Schema, Stream } from "effect"
 import { Database } from "../database/database"
 import { Bus } from "../bus"
 import { makeGlobalNode } from "@opencode-ai/util/effect/app-node"
+import { Agent } from "../agent"
 import { Model } from "../model"
 import { SessionEvent } from "./event"
 import { SessionMessage } from "./message"
@@ -230,6 +231,17 @@ function run(db: DatabaseService, event: MessageEvent) {
     }
     const appendMessage = (message: SessionMessage.Info) => insertMessage(db, event, message)
     const adapter: SessionMessageUpdater.Adapter = {
+      getAgent() {
+        return db
+          .select({ agent: SessionTable.agent })
+          .from(SessionTable)
+          .where(eq(SessionTable.id, event.data.sessionID))
+          .get()
+          .pipe(
+            Effect.orDie,
+            Effect.map((row) => (row?.agent ? Agent.ID.make(row.agent) : undefined)),
+          )
+      },
       getModel() {
         return db
           .select({ model: SessionTable.model })
@@ -398,12 +410,15 @@ const layer = Layer.effectDiscard(
       db.delete(SessionTable).where(eq(SessionTable.id, event.data.sessionID)).run().pipe(Effect.orDie),
     )
     yield* bus.project(SessionEvent.AgentSelected, (event) =>
-      db
-        .update(SessionTable)
-        .set({ agent: event.data.agent, time_updated: DateTime.toEpochMillis(event.created) })
-        .where(eq(SessionTable.id, event.data.sessionID))
-        .run()
-        .pipe(Effect.orDie, Effect.andThen(run(db, event))),
+      Effect.gen(function* () {
+        yield* run(db, event)
+        yield* db
+          .update(SessionTable)
+          .set({ agent: event.data.agent, time_updated: DateTime.toEpochMillis(event.created) })
+          .where(eq(SessionTable.id, event.data.sessionID))
+          .run()
+          .pipe(Effect.orDie)
+      }),
     )
     yield* bus.project(SessionEvent.ModelSelected, (event) =>
       Effect.gen(function* () {

packages/core/src/session/runner/to-llm-message.ts

@@ -59,6 +59,25 @@ const attachmentContent = (file: FileAttachment): ContentPart[] => {
   return []
 }
 
+const userAttachmentContent = (files: readonly FileAttachment[]) => {
+  const eligible = files.filter(
+    (file) => imageMimes.has(file.mime) && file.source.type === "inline" && file.mention?.text,
+  )
+  if (eligible.length < 2) return files.flatMap(attachmentContent)
+
+  const seen = new Map<string, string[]>()
+  return files.flatMap((file) => {
+    if (!imageMimes.has(file.mime) || file.source.type !== "inline" || !file.mention?.text)
+      return attachmentContent(file)
+    const metadata = JSON.stringify([file.mime, file.name ?? null, file.description ?? null, file.mention.text])
+    const matches = seen.get(metadata)
+    if (matches?.includes(file.data)) return []
+    if (matches) matches.push(file.data)
+    if (!matches) seen.set(metadata, [file.data])
+    return attachmentContent(file)
+  })
+}
+
 const decodeToolInput = Schema.decodeUnknownOption(Schema.UnknownFromJsonString)
 
 const providerMetadata = (
@@ -186,7 +205,7 @@ function toLLMMessage(message: SessionMessage.Info, model: Model.Ref, providerMe
       const content = [
         ...(message.skills ?? []).map((skill) => Message.text(skill.text)),
         ...(message.text === "" ? [] : [Message.text(message.text)]),
-        ...(message.files ?? []).flatMap(attachmentContent),
+        ...userAttachmentContent(message.files ?? []),
       ]
       if (content.length === 0) return []
       return [

packages/core/test/github-copilot/copilot-chat-model.test.ts

@@ -204,7 +204,7 @@ describe("doStream", () => {
       finishReason: { unified: "tool-calls" },
       usage: {
         inputTokens: { total: 19581 },
-        outputTokens: { total: 53 },
+        outputTokens: { total: 187, reasoning: 134 },
       },
     })
   })
@@ -259,7 +259,7 @@ describe("doStream", () => {
       finishReason: { unified: "stop" },
       usage: {
         inputTokens: { total: 5778 },
-        outputTokens: { total: 59 },
+        outputTokens: { total: 154, reasoning: 95 },
       },
       providerMetadata: {
         copilot: {
@@ -391,7 +391,7 @@ describe("doStream", () => {
       finishReason: { unified: "tool-calls" },
       usage: {
         inputTokens: { total: 3767 },
-        outputTokens: { total: 19 },
+        outputTokens: { total: 30, reasoning: 11 },
       },
     })
   })

packages/core/test/session-create.test.ts

@@ -647,7 +647,7 @@ describe("Session.create", () => {
   it.effect("switches the selected agent through the durable Session event", () =>
     Effect.gen(function* () {
       const session = yield* Session.Service
-      const created = yield* session.create({ location })
+      const created = yield* session.create({ location, agent: Agent.ID.make("build") })
 
       yield* session.switchAgent({ sessionID: created.id, agent: Agent.ID.make("plan") })
 
@@ -655,6 +655,9 @@ describe("Session.create", () => {
       expect(
         Array.from(yield* logEvents(session, created.id, true).pipe(Stream.drop(1), Stream.take(1), Stream.runCollect)),
       ).toMatchObject([{ type: "session.agent.selected", data: { agent: "plan" } }])
+      expect(yield* session.messages({ sessionID: created.id, order: "asc" })).toMatchObject([
+        { type: "agent-switched", agent: "plan", previous: "build" },
+      ])
     }),
   )
 

packages/core/test/session-projector.test.ts

@@ -358,6 +358,7 @@ describe("SessionProjector", () => {
           directory: "/project",
           title: "test",
           version: "test",
+          agent: "plan",
           model: previousModel,
         })
         .run()
@@ -459,6 +460,10 @@ describe("SessionProjector", () => {
         text: "synthetic context",
         metadata: { source: "projector-test" },
       })
+      expect(messages.find((message) => message.type === "agent-switched")).toMatchObject({
+        agent: build,
+        previous: "plan",
+      })
       expect(messages.find((message) => message.type === "model-switched")).toMatchObject({ previous: previousModel })
       expect(messages.find((message) => message.type === "shell")).toMatchObject({
         command: "pwd",

packages/core/test/session-runner-message.test.ts

@@ -373,6 +373,103 @@ Recent work
     ])
   })
 
+  test("deduplicates provider media while preserving durable attachment references", () => {
+    const data = Base64.make("AAECAw==")
+    const messages = toLLMMessages(
+      [
+        SessionMessage.User.make({
+          id: id("user-duplicate-image"),
+          type: "user",
+          text: "[Image 1] [Image 1] [Image 2]",
+          files: [
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+              mention: { start: 0, end: 9, text: "[Image 1]" },
+            }),
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+              mention: { start: 10, end: 19, text: "[Image 1]" },
+            }),
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+              description: "alternate use",
+              mention: { start: 20, end: 29, text: "[Image 2]" },
+            }),
+          ],
+          time: { created },
+        }),
+      ],
+      model,
+    )
+
+    expect(messages[0]?.content).toEqual([
+      { type: "text", text: "[Image 1] [Image 1] [Image 2]" },
+      { type: "media", mediaType: "image/png", data, filename: "image.png" },
+      {
+        type: "media",
+        mediaType: "image/png",
+        data,
+        filename: "image.png",
+        metadata: { description: "alternate use" },
+      },
+    ])
+  })
+
+  test("preserves provider media with distinct labels or URI sources", () => {
+    const data = Base64.make("AAECAw==")
+    const messages = toLLMMessages(
+      [
+        SessionMessage.User.make({
+          id: id("user-distinct-images"),
+          type: "user",
+          text: "[Image 1] [Image 2]",
+          files: [
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+              mention: { start: 0, end: 9, text: "[Image 1]" },
+            }),
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+              mention: { start: 10, end: 19, text: "[Image 2]" },
+            }),
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "uri", uri: "file:///project/image.png" },
+              name: "image.png",
+              mention: { start: 0, end: 9, text: "[Image 1]" },
+            }),
+            FileAttachment.make({
+              data,
+              mime: "image/png",
+              source: { type: "inline" },
+              name: "image.png",
+            }),
+          ],
+          time: { created },
+        }),
+      ],
+      model,
+    )
+
+    expect(messages[0]?.content.filter((part) => part.type === "media")).toHaveLength(4)
+  })
+
   test("replays durable tool media into canonical tool messages without structured base64", () => {
     const messages = toLLMMessages(
       [

packages/protocol/openapi.json

@@ -12733,6 +12733,9 @@
           },
           "agent": {
             "type": "string"
+          },
+          "previous": {
+            "type": "string"
           }
         },
         "required": ["id", "time", "type", "agent"],

packages/protocol/src/groups/session.ts

@@ -341,6 +341,8 @@ export const makeSessionGroup = <I extends HttpApiMiddleware.AnyId, S>(sessionLo
           id: SessionMessage.ID.pipe(Schema.optional),
           command: Schema.String,
           arguments: Schema.String.pipe(Schema.optional),
+          agent: Agent.ID.pipe(Schema.optional),
+          model: Model.Ref.pipe(Schema.optional),
           files: PromptInput.Prompt.fields.files,
           agents: PromptInput.Prompt.fields.agents,
           skills: PromptInput.Prompt.fields.skills,

packages/schema/src/session-message.ts

@@ -42,6 +42,7 @@ export const AgentSelected = Schema.Struct({
   ...Base,
   type: Schema.tag("agent-switched"),
   agent: Agent.ID,
+  previous: Agent.ID.pipe(optional),
 }).annotate({ identifier: "Session.Message.AgentSelected" })
 
 export interface ModelSelected extends Schema.Schema.Type<typeof ModelSelected> {}

packages/server/src/handlers/session.ts

@@ -355,6 +355,8 @@ export const SessionHandler = HttpApiBuilder.group(Api, "server.session", (handl
                 id: ctx.payload.id,
                 command: ctx.payload.command,
                 arguments: ctx.payload.arguments,
+                agent: ctx.payload.agent,
+                model: ctx.payload.model,
                 files: ctx.payload.files,
                 agents: ctx.payload.agents,
                 skills: ctx.payload.skills,

packages/tui/src/component/prompt/index.tsx

@@ -60,6 +60,11 @@ import { Keymap, type KeymapCommand } from "../../context/keymap"
 import { abbreviateHome } from "../../runtime"
 import { PluginSlot } from "../../plugin/render"
 import type { SessionPending } from "@opencode-ai/schema/session-pending"
+import {
+  deduplicatePromptImages,
+  preserveMentionlessPromptAttachments,
+  promptAttachmentLabel,
+} from "../../prompt/attachment"
 import { DialogImagePreview } from "../dialog-image-preview"
 
 export type PromptProps = {
@@ -331,7 +336,7 @@ export function Prompt(props: PromptProps) {
   }
 
   const imageAttachments = createMemo(() =>
-    (store.prompt.files ?? []).filter((file) => typeof file.uri === "string" && file.uri.startsWith("data:image/")),
+    (deduplicatePromptImages(store.prompt.files) ?? []).filter((file) => file.uri.startsWith("data:image/")),
   )
   const imagePreviewHeight = createMemo(() => Math.max(4, Math.min(8, Math.floor(dimensions().height / 4))))
   const imagePreviewWidth = createMemo(() => imagePreviewHeight() * 2)
@@ -736,6 +741,7 @@ export function Prompt(props: PromptProps) {
     setStore(
       produce((draft) => {
         const newMap = new Map<number, PromptPartRef>()
+        const fileExtmarks = new Map<number, NonNullable<PromptInfo["files"]>[number]>()
         const files: NonNullable<PromptInfo["files"]> = []
         const agents: NonNullable<PromptInfo["agents"]> = []
         const skills: NonNullable<PromptInfo["skills"]> = []
@@ -749,9 +755,8 @@ export function Prompt(props: PromptProps) {
             if (!part?.mention) continue
             part.mention.start = extmark.start
             part.mention.end = extmark.end
-            const index = files.length
             files.push(part)
-            newMap.set(extmark.id, { type: "file", index })
+            fileExtmarks.set(extmark.id, part)
             continue
           }
           if (ref.type === "agent") {
@@ -783,8 +788,19 @@ export function Prompt(props: PromptProps) {
           newMap.set(extmark.id, { type: "pasted", index })
         }
 
+        const nextFiles = preserveMentionlessPromptAttachments(draft.prompt.files, files)
+        const fileIndices = new Map(nextFiles.map((file, index) => [file, index]))
+        for (const [extmark, file] of fileExtmarks) {
+          const index = fileIndices.get(file)
+          if (index !== undefined) newMap.set(extmark, { type: "file", index })
+        }
+
         draft.extmarkToPart = newMap
-        draft.prompt.files = files
+        if (
+          nextFiles.length !== draft.prompt.files?.length ||
+          nextFiles.some((file, index) => file !== draft.prompt.files?.[index])
+        )
+          draft.prompt.files = nextFiles
         draft.prompt.agents = agents
         draft.prompt.skills = skills
         draft.prompt.pasted = pasted
@@ -1138,7 +1154,6 @@ export function Prompt(props: PromptProps) {
 
     // Capture mode before it gets reset
     const currentMode = store.mode
-
     if (store.mode === "shell") {
       move.startSubmit()
       void client.api.session.shell({
@@ -1149,23 +1164,15 @@ export function Prompt(props: PromptProps) {
     } else if (slashHead && isCommand) {
       move.startSubmit()
       const model = { providerID: selection.providerID, id: selection.modelID, variant }
-      if (session?.agent !== agent.id) await client.api.session.switchAgent({ sessionID, agent: agent.id })
       const cancelCommit = local.model.trackSessionCommit(sessionID, model)
-      if (
-        session?.model?.providerID !== model.providerID ||
-        session.model.id !== model.id ||
-        (session.model.variant ?? "default") !== (model.variant ?? "default")
-      )
-        await client.api.session.switchModel({ sessionID, model }).catch((error) => {
-          cancelCommit()
-          throw error
-        })
 
       void client.api.session
         .command({
           sessionID,
           command: slashHead.name,
           arguments: slashHead.arguments,
+          agent: agent.id,
+          model,
           files: store.prompt.files,
           agents: store.prompt.agents,
           skills: store.prompt.skills?.length ? store.prompt.skills : undefined,
@@ -1384,13 +1391,7 @@ export function Prompt(props: PromptProps) {
   function pasteAttachment(file: { filename?: string; uri: string }) {
     const currentOffset = input.cursorOffset
     const extmarkStart = currentOffset
-    const pdf = file.uri.startsWith("data:application/pdf;")
-    const count = pdf
-      ? (store.prompt.files?.filter(
-          (attachment) => typeof attachment.uri === "string" && attachment.uri.startsWith("data:application/pdf;"),
-        ).length ?? 0)
-      : imageAttachments().length
-    const virtualText = pdf ? `[PDF ${count + 1}]` : `[Image ${count + 1}]`
+    const virtualText = promptAttachmentLabel(store.prompt.files, { uri: file.uri, name: file.filename })
     const extmarkEnd = extmarkStart + virtualText.length
     const textToInsert = virtualText + " "
 

packages/tui/src/context/data.tsx

@@ -386,7 +386,8 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
             },
           }))
           break
-        case "session.agent.selected":
+        case "session.agent.selected": {
+          const previous = store.session.info[event.data.sessionID]?.agent
           if (store.session.info[event.data.sessionID])
             setStore("session", "info", event.data.sessionID, "agent", event.data.agent)
           message.update(event.data.sessionID, (draft, index) => {
@@ -394,10 +395,12 @@ export const { use: useData, provider: DataProvider } = createSimpleContext({
               id: messageIDFromEvent(event.id),
               type: "agent-switched",
               agent: event.data.agent,
+              previous,
               time: { created: event.created },
             })
           })
           break
+        }
         case "session.model.selected":
           if (store.session.info[event.data.sessionID])
             setStore("session", "info", event.data.sessionID, "model", event.data.model)

packages/tui/src/mini/stream-v2.transport.ts

@@ -1653,6 +1653,8 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
       )
     }
 
+    const selected = await resolveSelectedModel(input, client, next)
+    if (next.variant && !selected) throw new Error("Cannot select a variant before selecting a model")
     input.trace?.write("send.command", { sessionID: input.sessionID, messageID, command: command.name, delivery })
     return client.session.command(
       {
@@ -1660,6 +1662,8 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
         id: messageID,
         command: command.name,
         arguments: command.arguments,
+        agent: next.agent,
+        model: selected,
         files: attachments.files.length ? attachments.files : undefined,
         agents: agents.length ? agents : undefined,
         skills: skills.length ? skills : undefined,
@@ -1702,10 +1706,12 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
       const client = sdk
       if (next.agent)
         await client.session.switchAgent({ sessionID: input.sessionID, agent: next.agent }, { signal: next.signal })
-      const selected = await resolveSelectedModel(input, client, next)
-      if (next.variant && !selected) throw new Error("Cannot select a variant before selecting a model")
-      if (selected)
-        await client.session.switchModel({ sessionID: input.sessionID, model: selected }, { signal: next.signal })
+      if (!next.prompt.command) {
+        const selected = await resolveSelectedModel(input, client, next)
+        if (next.variant && !selected) throw new Error("Cannot select a variant before selecting a model")
+        if (selected)
+          await client.session.switchModel({ sessionID: input.sessionID, model: selected }, { signal: next.signal })
+      }
       mergePending(await admitPrompt(next, client, delivery))
       settlementClient = client
     },
@@ -1744,12 +1750,6 @@ export async function createSessionTransport(input: StreamInput): Promise<Sessio
         return
       }
       if (command) {
-        if (next.agent)
-          await client.session.switchAgent({ sessionID: input.sessionID, agent: next.agent }, { signal: next.signal })
-        const selected = await resolveSelectedModel(input, client, next)
-        if (next.variant && !selected) throw new Error("Cannot select a variant before selecting a model")
-        if (selected)
-          await client.session.switchModel({ sessionID: input.sessionID, model: selected }, { signal: next.signal })
         await runTurnWait(
           next,
           messageID,

packages/tui/src/prompt/attachment.ts

@@ -0,0 +1,96 @@
+import type { PromptInput } from "@opencode-ai/schema"
+
+type PromptFile = PromptInput.FileAttachment
+type PromptFileIdentity = Pick<PromptFile, "uri" | "name" | "description">
+type ProjectedFile = Readonly<{
+  data: string
+  mime: string
+  source: { type: string }
+  name?: string
+  description?: string
+  mention?: { text: string }
+}>
+
+function attachmentKind(uri: string) {
+  if (uri.startsWith("data:image/")) return "Image"
+  if (uri.startsWith("data:application/pdf;")) return "PDF"
+  return undefined
+}
+
+function attachmentMetadata(file: PromptFileIdentity) {
+  return JSON.stringify([file.name ?? null, file.description ?? null])
+}
+
+function deduplicateByIdentity<T>(
+  items: readonly T[],
+  identity: (item: T) => { metadata: string; payload: string } | undefined,
+) {
+  const seen = new Map<string, string[]>()
+  return items.filter((item) => {
+    const key = identity(item)
+    if (!key) return true
+    const matches = seen.get(key.metadata)
+    if (matches?.includes(key.payload)) return false
+    if (matches) matches.push(key.payload)
+    if (!matches) seen.set(key.metadata, [key.payload])
+    return true
+  })
+}
+
+export function deduplicatePromptImages(files: readonly PromptFile[] | undefined) {
+  if (!files || files.length < 2) return files
+  return deduplicateByIdentity(files, (file) =>
+    file.uri.startsWith("data:image/") && file.mention?.text
+      ? {
+          metadata: JSON.stringify([attachmentMetadata(file), file.mention.text]),
+          payload: file.uri,
+        }
+      : undefined,
+  )
+}
+
+export function preserveMentionlessPromptAttachments(
+  files: readonly PromptFile[] | undefined,
+  mentioned: PromptFile[],
+) {
+  if (!files) return mentioned
+  const tracked = mentioned.values()
+  return files.flatMap((file) => {
+    if (!file.mention?.text) return [file]
+    const next = tracked.next()
+    return next.done ? [] : [next.value]
+  })
+}
+
+export function deduplicateVisibleImages<T extends ProjectedFile>(files: readonly T[]) {
+  return deduplicateByIdentity(files, (file) =>
+    file.mime.startsWith("image/") && file.source.type === "inline" && file.mention?.text
+      ? {
+          metadata: JSON.stringify([file.mime, file.name ?? null, file.description ?? null, file.mention.text]),
+          payload: file.data,
+        }
+      : undefined,
+  )
+}
+
+export function promptAttachmentLabel(files: readonly PromptFile[] | undefined, file: PromptFileIdentity) {
+  const kind = attachmentKind(file.uri)
+  if (!kind) throw new Error(`Unsupported inline attachment: ${file.uri}`)
+  const metadata = attachmentMetadata(file)
+  const existing =
+    kind === "Image"
+      ? files?.find(
+          (candidate) =>
+            candidate.uri === file.uri && attachmentMetadata(candidate) === metadata && candidate.mention?.text,
+        )?.mention?.text
+      : undefined
+  if (existing) return existing
+
+  const pattern = new RegExp(`^\\[${kind} (\\d+)\\]$`)
+  const count =
+    files?.reduce((highest, candidate) => {
+      const match = candidate.mention?.text.match(pattern)
+      return match ? Math.max(highest, Number(match[1])) : highest
+    }, 0) ?? 0
+  return `[${kind} ${count + 1}]`
+}

packages/tui/src/routes/session/index.tsx

@@ -70,6 +70,7 @@ import stripAnsi from "strip-ansi"
 import { usePromptRef } from "../../context/prompt"
 import { sessionTabsFitVertically, SESSION_SIDEBAR_WIDTH } from "../../ui/layout"
 import { projectedPromptInput } from "../../prompt/codec"
+import { deduplicateVisibleImages } from "../../prompt/attachment"
 import { useEpilogue } from "../../context/epilogue"
 import { normalizePath } from "../../util/path"
 import { PermissionPrompt } from "./permission"
@@ -1651,7 +1652,12 @@ function SessionSwitchMessageV2(props: { message: SessionMessageInfo }) {
   const ctx = use()
   const theme = useTheme()
   const text = () => {
-    if (props.message.type === "agent-switched") return `Switched agent to ${props.message.agent}`
+    if (props.message.type === "agent-switched") {
+      const agent = Locale.titlecase(props.message.agent)
+      if (props.message.previous && props.message.previous !== props.message.agent)
+        return `Switched agent from ${Locale.titlecase(props.message.previous)} to ${agent}`
+      return `Switched agent to ${agent}`
+    }
     if (props.message.type === "model-switched")
       return switchLabel(props.message.model, ctx.models(), props.message.previous)
     return ""
@@ -1899,7 +1905,7 @@ function UserMessage(props: { message: SessionMessageUser }) {
   const ctx = use()
   const data = useData()
   const local = useLocal()
-  const files = createMemo(() => props.message.files ?? [])
+  const files = createMemo(() => deduplicateVisibleImages(props.message.files ?? []))
   const skills = createMemo(() => props.message.skills ?? [])
   const images = createMemo(() =>
     files().flatMap((file) =>

packages/tui/test/mini/stream-v2.transport.test.ts

@@ -2855,6 +2855,8 @@ describe("V2 mini transport", () => {
       id: "msg_cmd",
       command: "deploy",
       arguments: "prod",
+      agent: "build",
+      model: { providerID: "test", id: "model" },
       files: [
         { uri: "file:///tmp/context.txt", name: "context.txt" },
         {
@@ -2866,11 +2868,9 @@ describe("V2 mini transport", () => {
       skills: [{ id: "api-design", mention: { start: 13, end: 24, text: "/api-design" } }],
       delivery: "steer",
     })
-    expect(client.session.switchAgent).toHaveBeenCalledWith({ sessionID: "ses_1", agent: "build" }, expect.anything())
-    expect(client.session.switchModel).toHaveBeenCalledWith(
-      { sessionID: "ses_1", model: { providerID: "test", id: "model" } },
-      expect.anything(),
-    )
+    // Selection rides the command payload; no separate client-side switch.
+    expect(client.session.switchAgent).not.toHaveBeenCalled()
+    expect(client.session.switchModel).not.toHaveBeenCalled()
     await transport.close()
   })
 

packages/tui/test/prompt/attachment.test.ts

@@ -0,0 +1,125 @@
+import { describe, expect, test } from "bun:test"
+import {
+  deduplicatePromptImages,
+  deduplicateVisibleImages,
+  preserveMentionlessPromptAttachments,
+  promptAttachmentLabel,
+} from "../../src/prompt/attachment"
+
+describe("prompt attachments", () => {
+  test("deduplicates identical inline images while preserving other attachments", () => {
+    const files = [
+      {
+        uri: "data:image/png;base64,AAA",
+        name: "first.png",
+        mention: { start: 0, end: 9, text: "[Image 1]" },
+      },
+      { uri: "file:///same", name: "first.txt" },
+      { uri: "data:application/pdf;base64,CCC", name: "first.pdf" },
+      {
+        uri: "data:image/png;base64,BBB",
+        name: "second.png",
+        mention: { start: 10, end: 19, text: "[Image 2]" },
+      },
+      {
+        uri: "data:image/png;base64,AAA",
+        name: "first.png",
+        mention: { start: 20, end: 29, text: "[Image 1]" },
+      },
+      {
+        uri: "data:image/png;base64,AAA",
+        name: "first.png",
+        description: "alternate use",
+        mention: { start: 30, end: 39, text: "[Image 1]" },
+      },
+      { uri: "file:///same", name: "second.txt" },
+      { uri: "data:application/pdf;base64,CCC", name: "first.pdf" },
+    ]
+
+    expect(deduplicatePromptImages(files)).toEqual([
+      files[0],
+      files[1],
+      files[2],
+      files[3],
+      files[5],
+      files[6],
+      files[7],
+    ])
+    expect(files).toHaveLength(8)
+  })
+
+  test("reuses labels for identical image data", () => {
+    const first = "data:image/png;base64,AAA"
+    const second = "data:image/png;base64,BBB"
+    const files = [{ uri: first, mention: { start: 0, end: 9, text: "[Image 1]" } }]
+
+    expect(promptAttachmentLabel(files, { uri: first })).toBe("[Image 1]")
+    expect(promptAttachmentLabel([...files, { ...files[0], mention: undefined }], { uri: second })).toBe("[Image 2]")
+    expect(promptAttachmentLabel([{ uri: first }], { uri: first })).toBe("[Image 1]")
+  })
+
+  test("numbers PDFs independently from images", () => {
+    const files = [{ uri: "data:image/png;base64,AAA" }]
+
+    expect(promptAttachmentLabel(files, { uri: "data:application/pdf;base64,BBB" })).toBe("[PDF 1]")
+  })
+
+  test("does not reuse a label when attachment metadata differs", () => {
+    const uri = "data:image/png;base64,AAA"
+    const files = [{ uri, name: "one.png", mention: { start: 0, end: 9, text: "[Image 1]" } }]
+
+    expect(promptAttachmentLabel(files, { uri, name: "two.png" })).toBe("[Image 2]")
+  })
+
+  test("does not reuse numbers after an earlier attachment is removed", () => {
+    const files = [{ uri: "data:image/png;base64,BBB", mention: { start: 0, end: 9, text: "[Image 2]" } }]
+
+    expect(promptAttachmentLabel(files, { uri: "data:image/png;base64,CCC" })).toBe("[Image 3]")
+  })
+
+  test("preserves mentionless attachments when tracked mentions are synchronized", () => {
+    const mentionless = { uri: "data:image/png;base64,AAA" }
+    const emptyMention = {
+      uri: "data:image/png;base64,CCC",
+      mention: { start: 0, end: 0, text: "" },
+    }
+    const mentioned = {
+      uri: "data:image/png;base64,BBB",
+      mention: { start: 0, end: 9, text: "[Image 1]" },
+    }
+
+    const restored = preserveMentionlessPromptAttachments([mentionless, emptyMention, mentioned], [mentioned])
+    expect(restored).toEqual([mentionless, emptyMention, mentioned])
+    expect(restored.indexOf(mentioned)).toBe(2)
+
+    const another = {
+      uri: "data:image/png;base64,DDD",
+      mention: { start: 10, end: 19, text: "[Image 2]" },
+    }
+    expect(preserveMentionlessPromptAttachments([mentioned, mentionless, another], [another, mentioned])).toEqual([
+      another,
+      mentionless,
+      mentioned,
+    ])
+  })
+
+  test("deduplicates visible inline image cards without dropping durable references", () => {
+    const file = {
+      data: "AAA",
+      mime: "image/png",
+      source: { type: "inline" },
+      name: "clipboard",
+      mention: { text: "[Image 1]" },
+    }
+    const files = [file, { ...file, mention: { text: "[Image 1]" } }]
+
+    expect(deduplicateVisibleImages(files)).toEqual([file])
+    expect(files).toHaveLength(2)
+
+    const distinct = [
+      { ...file, mention: { text: "[Image 2]" } },
+      { ...file, mention: undefined },
+    ]
+    expect(deduplicateVisibleImages([file, ...distinct])).toEqual([file, ...distinct])
+  })
+})

packages/tui/test/prompt/history.test.ts

@@ -41,4 +41,21 @@ describe("prompt history", () => {
     const b = entry("describe this", [{ name: "b.png", uri: "data:image/png;base64,BBB" }])
     expect(isDuplicateEntry(a, b)).toBe(false)
   })
+
+  test("preserves duplicate attachment mentions for prompt restoration", () => {
+    const value = entry("[Image 1] [Image 1]", [
+      {
+        name: "clipboard",
+        uri: "data:image/png;base64,AAA",
+        mention: { start: 0, end: 9, text: "[Image 1]" },
+      },
+      {
+        name: "clipboard",
+        uri: "data:image/png;base64,AAA",
+        mention: { start: 10, end: 19, text: "[Image 1]" },
+      },
+    ])
+
+    expect(parsePromptHistory(JSON.stringify(value))).toEqual([value])
+  })
 })

packages/www/openapi.json

@@ -12733,6 +12733,9 @@
           },
           "agent": {
             "type": "string"
+          },
+          "previous": {
+            "type": "string"
           }
         },
         "required": ["id", "time", "type", "agent"],

packages/www/public/openapi.json

@@ -12733,6 +12733,9 @@
           },
           "agent": {
             "type": "string"
+          },
+          "previous": {
+            "type": "string"
           }
         },
         "required": ["id", "time", "type", "agent"],