Merge branch 'v2' into empty-variants

Co-authored-by: Aiden Cline <rekram1-node@users.noreply.github.com>
Co-authored-by: Aiden Cline <63023139+rekram1-node@users.noreply.github.com>

packages/ai/src/protocols/anthropic-messages.ts

@@ -30,7 +30,6 @@ import { ToolSchemaProjection } from "./utils/tool-schema.js"
 import { ToolStream } from "./utils/tool-stream.js"
 
 const ADAPTER = "anthropic-messages"
-const MEDIA_MIMES = new Set<string>([...ProviderShared.IMAGE_MIMES, ...ProviderShared.PDF_MIMES])
 export const DEFAULT_BASE_URL = "https://api.anthropic.com/v1"
 export const PATH = "/messages"
 
@@ -400,7 +399,7 @@ const lowerServerToolResult = Effect.fn("AnthropicMessages.lowerServerToolResult
 })
 
 const lowerMedia = Effect.fn("AnthropicMessages.lowerMedia")(function* (part: MediaPart) {
-  const media = yield* ProviderShared.validateMedia("Anthropic Messages", part, MEDIA_MIMES)
+  const media = ProviderShared.normalizeMedia(part)
   if (media.mime === "application/pdf")
     return {
       type: "document" as const,
@@ -410,6 +409,8 @@ const lowerMedia = Effect.fn("AnthropicMessages.lowerMedia")(function* (part: Me
         data: media.base64,
       },
     } satisfies AnthropicDocumentBlock
+  if (!media.mime.startsWith("image/"))
+    return yield* invalid(`Anthropic Messages does not support media type ${part.mediaType}`)
   return {
     type: "image" as const,
     source: {

packages/ai/src/protocols/gemini.ts

@@ -24,7 +24,6 @@ import { Lifecycle } from "./utils/lifecycle.js"
 import { ToolSchemaProjection } from "./utils/tool-schema.js"
 
 const ADAPTER = "gemini"
-const MEDIA_MIMES = new Set<string>(ProviderShared.MEDIA_MIMES)
 // Google documents this sentinel for replaying Gemini 3 function calls after their original signature was lost.
 const SKIP_THOUGHT_SIGNATURE_VALIDATOR = "skip_thought_signature_validator"
 export const DEFAULT_BASE_URL = "https://generativelanguage.googleapis.com/v1beta"
@@ -248,7 +247,7 @@ const lowerToolConfig = (toolChoice: NonNullable<LLMRequest["toolChoice"]>) =>
 
 const lowerUserPart = Effect.fn("Gemini.lowerUserPart")(function* (part: TextPart | MediaPart) {
   if (part.type === "text") return { text: part.text }
-  const media = yield* ProviderShared.validateMedia("Gemini", part, MEDIA_MIMES)
+  const media = ProviderShared.normalizeMedia(part)
   return { inlineData: { mimeType: media.mime, data: media.base64 } }
 })
 
@@ -353,7 +352,7 @@ const lowerMessages = Effect.fn("Gemini.lowerMessages")(function* (request: LLMR
       const media: GeminiInlineDataPart[] = []
       for (const item of content) {
         if (item.type === "text") continue
-        const value = yield* ProviderShared.validateToolFile("Gemini", item, MEDIA_MIMES)
+        const value = ProviderShared.normalizeToolFile(item)
         media.push({ inlineData: { mimeType: value.mime, data: value.base64 } })
       }
       parts.push({

packages/ai/src/protocols/open-responses.ts

@@ -26,7 +26,6 @@ import { ToolStream } from "./utils/tool-stream.js"
 
 const ADAPTER = "open-responses"
 const NAME = "Open Responses"
-const MEDIA_MIMES = new Set<string>([...ProviderShared.IMAGE_MIMES, ...ProviderShared.PDF_MIMES])
 export const PATH = "/responses"
 
 // =============================================================================
@@ -285,7 +284,7 @@ export interface Extension {
   readonly name: string
   readonly lowerMedia?: (input: {
     readonly part: MediaPart
-    readonly media: ProviderShared.ValidatedMedia
+    readonly media: ProviderShared.NormalizedMedia
     readonly request: LLMRequest
   }) => MediaInput | undefined
   readonly messagePhase?: (value: unknown) => MessagePhase | null | undefined
@@ -380,13 +379,13 @@ const lowerMedia = Effect.fn("OpenResponses.lowerMedia")(function* (
   request: LLMRequest,
   extension: Extension,
 ) {
-  const media = yield* ProviderShared.validateMedia(extension.name, part, MEDIA_MIMES)
+  const media = ProviderShared.normalizeMedia(part)
   const extended = extension.lowerMedia?.({ part, media, request })
   if (extended) return extended
-  if (media.mime === "application/pdf") {
+  if (!media.mime.startsWith("image/")) {
     return {
       type: "input_file" as const,
-      filename: part.filename ?? "document.pdf",
+      filename: part.filename ?? (media.mime === "application/pdf" ? "document.pdf" : "file"),
       file_data: media.dataUrl,
     }
   }

packages/ai/src/protocols/openai-chat.ts

@@ -28,7 +28,6 @@ import { ToolSchemaProjection } from "./utils/tool-schema.js"
 import { ToolStream } from "./utils/tool-stream.js"
 
 const ADAPTER = "openai-chat"
-const IMAGE_MIMES = new Set<string>(ProviderShared.IMAGE_MIMES)
 const RESERVED_REASONING_FIELDS = new Set(["role", "content", "tool_calls"])
 export const DEFAULT_BASE_URL = "https://api.openai.com/v1"
 export const PATH = "/chat/completions"
@@ -284,7 +283,9 @@ const lowerToolCall = (part: ToolCallPart): OpenAIChatAssistantToolCall => ({
 })
 
 const lowerMedia = Effect.fn("OpenAIChat.lowerMedia")(function* (part: MediaPart) {
-  const media = yield* ProviderShared.validateMedia("OpenAI Chat", part, IMAGE_MIMES)
+  const media = ProviderShared.normalizeMedia(part)
+  if (!media.mime.startsWith("image/"))
+    return yield* ProviderShared.invalidRequest(`OpenAI Chat does not support media type ${part.mediaType}`)
   return { type: "image_url" as const, image_url: { url: media.dataUrl } }
 })
 

packages/ai/src/protocols/shared.ts

@@ -155,59 +155,24 @@ export const wrappedSystemUpdate = Effect.fn("ProviderShared.wrappedSystemUpdate
 export const parseToolInput = (route: string, name: string, raw: string) =>
   parseJson(route, raw || "{}", `Invalid JSON input for ${route} tool call ${name}`)
 
-export const IMAGE_MIMES = ["image/png", "image/jpeg", "image/gif", "image/webp"] as const
-export const VIDEO_MIMES = ["video/mp4", "video/webm", "video/quicktime"] as const
-export const AUDIO_MIMES = ["audio/wav", "audio/mp3", "audio/aiff", "audio/aac", "audio/ogg", "audio/flac"] as const
-export const PDF_MIMES = ["application/pdf"] as const
-export const MEDIA_MIMES = [...IMAGE_MIMES, ...VIDEO_MIMES, ...AUDIO_MIMES, ...PDF_MIMES] as const
-export const MAX_MEDIA_ENCODED_BYTES = 28 * 1024 * 1024
-export const MAX_MEDIA_DECODED_BYTES = 20 * 1024 * 1024
-
-const base64Pattern = /^(?:[A-Za-z0-9+/]{4})*(?:[A-Za-z0-9+/]{2}==|[A-Za-z0-9+/]{3}=)?$/
-
-export interface ValidatedMedia {
+export interface NormalizedMedia {
   readonly mime: string
   readonly base64: string
   readonly dataUrl: string
-  readonly bytes: Uint8Array
 }
 
-export const validateMedia = Effect.fn("ProviderShared.validateMedia")(function* (
-  route: string,
-  part: MediaPart,
-  supportedMimes: ReadonlySet<string>,
-) {
+export const normalizeMedia = (part: MediaPart): NormalizedMedia => {
   const mime = part.mediaType.toLowerCase()
-  if (!supportedMimes.has(mime)) return yield* invalidRequest(`${route} does not support media type ${part.mediaType}`)
-
-  let base64: string
   if (typeof part.data !== "string") {
-    if (part.data.byteLength > MAX_MEDIA_DECODED_BYTES)
-      return yield* invalidRequest(`${route} media exceeds the ${MAX_MEDIA_DECODED_BYTES} byte decoded limit`)
-    base64 = Buffer.from(part.data).toString("base64")
-  } else if (part.data.startsWith("data:")) {
-    const match = /^data:([^;,]+);base64,([A-Za-z0-9+/]*={0,2})$/s.exec(part.data)
-    if (!match) return yield* invalidRequest(`${route} media data URL must contain valid base64`)
-    if (match[1]!.toLowerCase() !== mime)
-      return yield* invalidRequest(`${route} media type ${part.mediaType} does not match data URL type ${match[1]}`)
-    base64 = match[2]!
-  } else {
-    base64 = part.data
+    const base64 = Buffer.from(part.data).toString("base64")
+    return { mime, base64, dataUrl: `data:${mime};base64,${base64}` }
   }
+  if (!part.data.startsWith("data:")) return { mime, base64: part.data, dataUrl: `data:${mime};base64,${part.data}` }
+  return { mime, base64: part.data.slice(part.data.indexOf(",") + 1), dataUrl: part.data }
+}
 
-  if (Buffer.byteLength(base64, "utf8") > MAX_MEDIA_ENCODED_BYTES)
-    return yield* invalidRequest(`${route} media exceeds the ${MAX_MEDIA_ENCODED_BYTES} byte encoded limit`)
-  if (!base64 || base64.length % 4 !== 0 || !base64Pattern.test(base64))
-    return yield* invalidRequest(`${route} media must contain valid base64`)
-  const bytes = Buffer.from(base64, "base64")
-  if (bytes.byteLength > MAX_MEDIA_DECODED_BYTES)
-    return yield* invalidRequest(`${route} media exceeds the ${MAX_MEDIA_DECODED_BYTES} byte decoded limit`)
-  if (bytes.toString("base64") !== base64) return yield* invalidRequest(`${route} media must contain canonical base64`)
-  return { mime, base64, dataUrl: `data:${mime};base64,${base64}`, bytes } satisfies ValidatedMedia
-})
-
-export const validateToolFile = (route: string, part: Tool.FileContent, supportedMimes: ReadonlySet<string>) =>
-  validateMedia(route, { type: "media", mediaType: part.mime, data: part.uri, filename: part.name }, supportedMimes)
+export const normalizeToolFile = (part: Tool.FileContent) =>
+  normalizeMedia({ type: "media", mediaType: part.mime, data: part.uri, filename: part.name })
 
 export const trimBaseUrl = (value: string) => value.replace(/\/+$/, "")
 

packages/ai/src/protocols/utils/bedrock-media.ts

@@ -66,11 +66,7 @@ export const lower = Effect.fn("BedrockMedia.lower")(function* (part: MediaPart)
   const mime = part.mediaType.toLowerCase()
   const imageFormat = IMAGE_FORMATS[mime as keyof typeof IMAGE_FORMATS]
   if (imageFormat) {
-    const media = yield* ProviderShared.validateMedia(
-      "Bedrock Converse",
-      part,
-      new Set<string>(Object.keys(IMAGE_FORMATS)),
-    )
+    const media = ProviderShared.normalizeMedia(part)
     return { image: { format: imageFormat, source: { bytes: media.base64 } } } satisfies ImageBlock
   }
   if (mime.startsWith("image/"))
@@ -79,11 +75,7 @@ export const lower = Effect.fn("BedrockMedia.lower")(function* (part: MediaPart)
   if (documentFormat) {
     if (!part.filename)
       return yield* ProviderShared.invalidRequest("Bedrock Converse document media requires a filename")
-    const media = yield* ProviderShared.validateMedia(
-      "Bedrock Converse",
-      part,
-      new Set<string>(Object.keys(DOCUMENT_FORMATS)),
-    )
+    const media = ProviderShared.normalizeMedia(part)
     return documentBlock(part.filename, documentFormat, media.base64)
   }
   return yield* ProviderShared.invalidRequest(`Bedrock Converse does not support media type ${part.mediaType}`)

packages/ai/test/provider/anthropic-messages.test.ts

@@ -399,7 +399,7 @@ describe("Anthropic Messages route", () => {
     }),
   )
 
-  it.effect("rejects unsupported media in tool-result content with a clear error", () =>
+  it.effect("rejects tool-result media that cannot be lowered", () =>
     Effect.gen(function* () {
       const error = yield* compileRequest(
         LLM.request({
@@ -418,8 +418,7 @@ describe("Anthropic Messages route", () => {
         }),
       ).pipe(Effect.flip)
 
-      expect(error.message).toContain("Anthropic Messages")
-      expect(error.message).toContain("audio/mpeg")
+      expect(error.message).toContain("Anthropic Messages does not support media type audio/mpeg")
     }),
   )
 

packages/ai/test/provider/gemini.test.ts

@@ -4,7 +4,6 @@ import { LLM, AIError, LLMRequest, Message, ToolCallPart, ToolDefinition, Usage
 import { Auth, LLMClient } from "../../src/route.js"
 import { compileRequest } from "../../src/route/client.js"
 import * as Gemini from "../../src/protocols/gemini.js"
-import { ProviderShared } from "../../src/protocols/shared.js"
 import { it } from "../lib/effect.js"
 import { fixedResponse } from "../lib/http.js"
 import { sseEvents, sseRaw } from "../lib/sse.js"
@@ -291,35 +290,30 @@ describe("Gemini route", () => {
     }),
   )
 
-  for (const [name, media] of [
-    ["mismatched data URL MIME", { mediaType: "image/png", data: "data:image/jpeg;base64,/9j/" }],
-    ["malformed base64", { mediaType: "image/png", data: "%%%=" }],
-    ["unsupported SVG", { mediaType: "image/svg+xml", data: "PHN2Zz4=" }],
-  ] as const)
-    it.effect(`rejects ${name}`, () =>
-      Effect.gen(function* () {
-        const error = yield* compileRequest(
-          LLM.request({ model, messages: [Message.user({ type: "media", ...media })] }),
-        ).pipe(Effect.flip)
-        expect(error.message).toMatch(/does not support|does not match|valid base64/)
-      }),
-    )
-
-  it.effect("rejects oversized image input", () =>
+  it.effect("passes encoded media through without local validation", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const prepared = yield* compileRequest(
         LLM.request({
           model,
           messages: [
-            Message.user({
-              type: "media",
-              mediaType: "image/png",
-              data: "A".repeat(ProviderShared.MAX_MEDIA_ENCODED_BYTES + 4),
-            }),
+            Message.user([
+              { type: "media", mediaType: "image/png", data: "%%%=" },
+              { type: "media", mediaType: "image/png", data: "data:image/jpeg;base64,/9j/" },
+              { type: "media", mediaType: "image/svg+xml", data: "PHN2Zz4=" },
+            ]),
           ],
         }),
-      ).pipe(Effect.flip)
-      expect(error.message).toContain("encoded limit")
+      )
+      expect(prepared.body.contents).toEqual([
+        {
+          role: "user",
+          parts: [
+            { inlineData: { mimeType: "image/png", data: "%%%=" } },
+            { inlineData: { mimeType: "image/png", data: "/9j/" } },
+            { inlineData: { mimeType: "image/svg+xml", data: "PHN2Zz4=" } },
+          ],
+        },
+      ])
     }),
   )
 

packages/ai/test/provider/openai-chat.test.ts

@@ -527,35 +527,42 @@ describe("OpenAI Chat route", () => {
     }),
   )
 
-  for (const [name, media] of [
-    ["mismatched data URL MIME", { mediaType: "image/png", data: "data:image/jpeg;base64,/9j/" }],
-    ["malformed base64", { mediaType: "image/png", data: "not-base64" }],
-    ["unsupported SVG", { mediaType: "image/svg+xml", data: "PHN2Zz4=" }],
-  ] as const)
-    it.effect(`rejects ${name}`, () =>
-      Effect.gen(function* () {
-        const error = yield* compileRequest(
-          LLM.request({ model, messages: [Message.user({ type: "media", ...media })] }),
-        ).pipe(Effect.flip)
-        expect(error.message).toMatch(/does not support|does not match|valid base64/)
-      }),
-    )
+  it.effect("passes encoded image media through without local validation", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          model,
+          messages: [
+            Message.user([
+              { type: "media", mediaType: "image/png", data: "not-base64" },
+              { type: "media", mediaType: "image/png", data: "data:image/jpeg;base64,/9j/" },
+              { type: "media", mediaType: "image/svg+xml", data: "PHN2Zz4=" },
+            ]),
+          ],
+        }),
+      )
+      expect(prepared.body.messages).toEqual([
+        {
+          role: "user",
+          content: [
+            { type: "image_url", image_url: { url: "data:image/png;base64,not-base64" } },
+            { type: "image_url", image_url: { url: "data:image/jpeg;base64,/9j/" } },
+            { type: "image_url", image_url: { url: "data:image/svg+xml;base64,PHN2Zz4=" } },
+          ],
+        },
+      ])
+    }),
+  )
 
-  it.effect("rejects oversized image input", () =>
+  it.effect("rejects non-image media that cannot be lowered", () =>
     Effect.gen(function* () {
       const error = yield* compileRequest(
         LLM.request({
           model,
-          messages: [
-            Message.user({
-              type: "media",
-              mediaType: "image/png",
-              data: "A".repeat(ProviderShared.MAX_MEDIA_ENCODED_BYTES + 4),
-            }),
-          ],
+          messages: [Message.user({ type: "media", mediaType: "audio/mpeg", data: "AAECAw==" })],
         }),
       ).pipe(Effect.flip)
-      expect(error.message).toContain("encoded limit")
+      expect(error.message).toContain("OpenAI Chat does not support media type audio/mpeg")
     }),
   )
 

packages/ai/test/provider/openai-responses.test.ts

@@ -1149,6 +1149,32 @@ describe("OpenAI Responses route", () => {
     }),
   )
 
+  it.effect("passes large PDF tool-result content through", () =>
+    Effect.gen(function* () {
+      const base64 = "A".repeat(8_125_844)
+      const dataUrl = `data:application/pdf;base64,${base64}`
+      const prepared = yield* compileRequest(
+        LLM.request({
+          id: "req_tool_result_large_pdf",
+          model,
+          messages: [
+            Message.assistant([ToolCallPart.make({ id: "call_1", name: "read", input: {} })]),
+            Message.tool({
+              id: "call_1",
+              name: "read",
+              resultType: "content",
+              result: [{ type: "file", uri: dataUrl, mime: "application/pdf", name: "report.pdf" }],
+            }),
+          ],
+        }),
+      )
+
+      expect(expectToolOutput(prepared.body).output).toEqual([
+        { type: "input_file", filename: "report.pdf", file_data: dataUrl },
+      ])
+    }),
+  )
+
   it.effect("uses xAI inline file encoding for PDF tool results", () =>
     Effect.gen(function* () {
       const prepared = yield* compileRequest(
@@ -1184,9 +1210,9 @@ describe("OpenAI Responses route", () => {
     }),
   )
 
-  it.effect("rejects unsupported media in tool-result content with a clear error", () =>
+  it.effect("passes non-image tool-result content through as an input file", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const prepared = yield* compileRequest(
         LLM.request({
           id: "req_tool_result_unsupported_media",
           model,
@@ -1200,10 +1226,11 @@ describe("OpenAI Responses route", () => {
             }),
           ],
         }),
-      ).pipe(Effect.flip)
+      )
 
-      expect(error.message).toContain("OpenAI Responses")
-      expect(error.message).toContain("audio/mpeg")
+      expect(expectToolOutput(prepared.body).output).toEqual([
+        { type: "input_file", filename: "file", file_data: "data:audio/mpeg;base64,AAECAw==" },
+      ])
     }),
   )
 
@@ -2394,17 +2421,28 @@ describe("OpenAI Responses route", () => {
     }),
   )
 
-  it.effect("rejects unsupported user media content", () =>
+  it.effect("passes non-image user media through as an input file", () =>
     Effect.gen(function* () {
-      const error = yield* compileRequest(
+      const prepared = yield* compileRequest(
         LLM.request({
           id: "req_media",
           model,
           messages: [Message.user({ type: "media", mediaType: "application/x-tar", data: "AAECAw==" })],
         }),
-      ).pipe(Effect.flip)
+      )
 
-      expect(error.message).toContain("OpenAI Responses does not support media type application/x-tar")
+      expect(prepared.body.input).toEqual([
+        {
+          role: "user",
+          content: [
+            {
+              type: "input_file",
+              filename: "file",
+              file_data: "data:application/x-tar;base64,AAECAw==",
+            },
+          ],
+        },
+      ])
     }),
   )
 

packages/core/src/aisdk.ts

@@ -435,7 +435,22 @@ function prompt(request: LLMRequest): LanguageModelV3Prompt {
     .map((part) => part.text)
     .filter(Boolean)
     .join("\n\n")
-  const messages = request.messages.flatMap(message)
+  const pending: UserContent = []
+  const messages = request.messages.flatMap((input, index) => {
+    if (input.role !== "tool") return message(input)
+    const lowered = toolMessage(input)
+    pending.push(...lowered.media)
+    if (request.messages[index + 1]?.role === "tool" || pending.length === 0) return lowered.messages
+    const media = [...pending]
+    pending.length = 0
+    return [
+      ...lowered.messages,
+      {
+        role: "user" as const,
+        content: [{ type: "text" as const, text: "Attached media from tool result:" }, ...media],
+      },
+    ]
+  })
   if (!system.length) return messages
   return [{ role: "system", content: system }, ...messages]
 }
@@ -448,10 +463,33 @@ function message(input: LLMRequest["messages"][number]): LanguageModelV3Message[
       return [{ role: "user", content: input.content.flatMap(userPart) }]
     case "assistant":
       return [{ role: "assistant", content: input.content.flatMap(assistantPart) }]
-    case "tool": {
-      const content = input.content.flatMap(toolResultPart)
-      return content.length ? [{ role: "tool", content }] : []
-    }
+    case "tool":
+      return toolMessage(input).messages
+  }
+}
+
+function toolMessage(input: LLMRequest["messages"][number]) {
+  const media: UserContent = []
+  const content = input.content.flatMap((part) => {
+    if (part.type !== "tool-result" || part.result.type !== "content") return toolResultPart(part)
+    const value = part.result.value.filter((item) => {
+      if (item.type !== "file") return true
+      if (!item.mime.startsWith("image/") && item.mime !== "application/pdf") return true
+      const data = /^data:[^;,]+(?:;[^,]*)*;base64,(.*)$/s.exec(item.uri)?.[1] ?? item.uri
+      media.push({ type: "file", mediaType: item.mime, data, filename: item.name })
+      return false
+    })
+    return toolResultPart({
+      ...part,
+      result:
+        value.length === 0
+          ? { type: "text", value: "Media attached in the following user message." }
+          : { ...part.result, value },
+    })
+  })
+  return {
+    messages: content.length ? ([{ role: "tool", content }] satisfies LanguageModelV3Message[]) : [],
+    media,
   }
 }
 

packages/core/src/plugin/plan.ts

@@ -1,6 +1,6 @@
 export * as PlanPlugin from "./plan.js"
 
-import { ToolFailure } from "@opencode-ai/ai"
+import { Message, ToolFailure } from "@opencode-ai/ai"
 import { define } from "@opencode-ai/plugin/effect/plugin"
 import { Effect, Stream } from "effect"
 import { Agent } from "../agent.js"
@@ -38,13 +38,33 @@ export const Plugin = define({
       })
     })
 
+    // Compaction and committed reverts can strip reminders while the session's agent stays
+    // put. Reconcile per request, appending near the tail so the cached prefix stays warm.
+    yield* ctx.session.hook("context", (event) => {
+      const reminder = lastReminder(event.messages)
+      const missing = event.agent === plan && reminder !== enter
+      const stale = event.agent !== plan && reminder === enter
+      const text = missing ? enter : stale ? leave : undefined
+      if (!text) return Effect.void
+      // Before the user's prompt, matching where agent-switch reminders land.
+      const at = event.messages.at(-1)?.role === "user" ? event.messages.length - 1 : event.messages.length
+      event.messages.splice(at, 0, Message.user(text))
+      return ctx.session
+        .synthetic({ sessionID: event.sessionID, text, resume: false })
+        .pipe(
+          Effect.catchCause((cause) =>
+            Effect.logWarning("failed to persist Plan mode reminder", { sessionID: event.sessionID, cause }),
+          ),
+        )
+    })
+
     yield* ctx.event.subscribe().pipe(
       Stream.filter(
         (event): event is SessionEvent.Created | SessionEvent.AgentSelected =>
           event.type === "session.created" || event.type === "session.agent.selected",
       ),
       Stream.runForEach((event) => {
-        const text = reminder(event)
+        const text = switchReminder(event)
         if (!text) return Effect.void
         return ctx.session
           .synthetic({
@@ -63,7 +83,7 @@ export const Plugin = define({
   }),
 })
 
-function reminder(event: SessionEvent.Created | SessionEvent.AgentSelected) {
+function switchReminder(event: SessionEvent.Created | SessionEvent.AgentSelected) {
   if (event.type === "session.created") {
     if (event.data.agent !== plan) return
     return enter
@@ -72,3 +92,11 @@ function reminder(event: SessionEvent.Created | SessionEvent.AgentSelected) {
   if (event.data.agent === plan) return enter
   if (event.data.previous === plan) return leave
 }
+
+function lastReminder(messages: ReadonlyArray<Message>) {
+  return messages.reduce<string | undefined>((found, message) => {
+    const part = message.role === "user" && message.content.length === 1 ? message.content[0] : undefined
+    if (part?.type !== "text") return found
+    return part.text === enter || part.text === leave ? part.text : found
+  }, undefined)
+}

packages/core/test/aisdk.test.ts

@@ -1,5 +1,6 @@
 import { APICallError } from "@ai-sdk/provider"
 import type { LanguageModelV3, LanguageModelV3StreamPart } from "@ai-sdk/provider"
+import { createMistral } from "@ai-sdk/mistral"
 import { AISDK } from "@opencode-ai/core/aisdk"
 import { SessionRunnerRetry } from "@opencode-ai/core/session/runner/retry"
 import { toSessionError } from "@opencode-ai/core/session/to-session-error"
@@ -277,67 +278,88 @@ it.effect("projects replay metadata onto AI SDK prompt parts", () =>
   }),
 )
 
-it.effect("preserves tool result content in AI SDK prompts", () =>
+it.effect("moves a tool image through the real Mistral provider as a user message", () =>
   Effect.gen(function* () {
     const aisdk = yield* AISDK.Service
+    let body: { messages?: unknown[] } | undefined
+    const mockFetch = Object.assign(
+      async (_input: Parameters<typeof fetch>[0], init?: RequestInit) => {
+        body = JSON.parse(String(init?.body))
+        const chunks = [
+          {
+            id: "response-1",
+            created: 0,
+            model: "pixtral-large-latest",
+            choices: [{ index: 0, delta: { content: [{ type: "text", text: "I see it." }] } }],
+          },
+          {
+            id: "response-1",
+            created: 0,
+            model: "pixtral-large-latest",
+            choices: [{ index: 0, delta: {}, finish_reason: "stop" }],
+            usage: { prompt_tokens: 1, completion_tokens: 1, total_tokens: 2 },
+          },
+        ]
+        return new Response(chunks.map((chunk) => `data: ${JSON.stringify(chunk)}\n\n`).join(""), {
+          headers: { "Content-Type": "text/event-stream" },
+        })
+      },
+      { preconnect: fetch.preconnect },
+    )
     yield* aisdk.hook.sdk((event) => {
-      event.sdk = { languageModel: () => ({ provider: event.model.providerID }) }
+      event.sdk = createMistral({ apiKey: "test", fetch: mockFetch })
     })
 
-    const resolved = yield* aisdk.model(model("test-ai-sdk"))
-    const prepared = yield* compileRequest(
+    const resolved = yield* aisdk.model({
+      ...model("@ai-sdk/mistral"),
+      modelID: Model.ID.make("pixtral-large-latest"),
+    })
+    yield* LLMClient.generate(
       LLM.request({
         model: resolved,
         messages: [
+          Message.user("Inspect the screenshot."),
+          Message.assistant({ type: "tool-call", id: "call_1", name: "screenshot", input: {} }),
           Message.tool({
+            type: "tool-result",
             id: "call_1",
-            name: "read",
+            name: "screenshot",
             result: {
               type: "content",
               value: [
-                { type: "text", text: "attachments" },
-                { type: "file", uri: "data:image/png;base64,AAAA", mime: "image/png", name: "pixel.png" },
-                {
-                  type: "file",
-                  uri: "data:application/pdf;charset=utf-8;base64,JVBERg==",
-                  mime: "application/pdf",
-                  name: "document.pdf",
-                },
-                { type: "file", uri: "data:audio/mpeg;base64,SUQz", mime: "audio/mpeg", name: "clip.mp3" },
-                { type: "file", uri: "https://example.com/pixel.png", mime: "image/png" },
-                { type: "file", uri: "https://example.com/document.pdf", mime: "application/pdf" },
+                { type: "text", text: "Screenshot captured" },
+                { type: "file", uri: "data:image/png;base64,AAAA", mime: "image/png", name: "screen.png" },
               ],
             },
           }),
         ],
       }),
-    )
+    ).pipe(Effect.provide(client))
 
-    expect(prepared.body.prompt).toEqual([
+    expect(body?.messages).toEqual([
+      { role: "user", content: [{ type: "text", text: "Inspect the screenshot." }] },
+      {
+        role: "assistant",
+        content: "",
+        tool_calls: [
+          {
+            id: "call_1",
+            type: "function",
+            function: { name: "screenshot", arguments: "{}" },
+          },
+        ],
+      },
       {
         role: "tool",
+        name: "screenshot",
+        tool_call_id: "call_1",
+        content: '[{"type":"text","text":"Screenshot captured"}]',
+      },
+      {
+        role: "user",
         content: [
-          {
-            type: "tool-result",
-            toolCallId: "call_1",
-            toolName: "read",
-            output: {
-              type: "content",
-              value: [
-                { type: "text", text: "attachments" },
-                { type: "image-data", data: "AAAA", mediaType: "image/png" },
-                {
-                  type: "file-data",
-                  data: "JVBERg==",
-                  mediaType: "application/pdf",
-                  filename: "document.pdf",
-                },
-                { type: "file-data", data: "SUQz", mediaType: "audio/mpeg", filename: "clip.mp3" },
-                { type: "image-url", url: "https://example.com/pixel.png" },
-                { type: "file-url", url: "https://example.com/document.pdf" },
-              ],
-            },
-          },
+          { type: "text", text: "Attached media from tool result:" },
+          { type: "image_url", image_url: "data:image/png;base64,AAAA" },
         ],
       },
     ])

packages/core/test/plugin/plan.test.ts

@@ -0,0 +1,180 @@
+import { describe, expect } from "bun:test"
+import { Message } from "@opencode-ai/ai"
+import { DateTime, Effect, Stream } from "effect"
+import type { SessionContext } from "@opencode-ai/plugin/effect/session"
+import { Agent } from "@opencode-ai/core/agent"
+import { Event } from "@opencode-ai/schema/event"
+import { Model } from "@opencode-ai/core/model"
+import { PlanPlugin } from "@opencode-ai/core/plugin/plan"
+import { Provider } from "@opencode-ai/core/provider"
+import { Session } from "@opencode-ai/core/session"
+import { SessionEvent } from "@opencode-ai/core/session/event"
+import { SessionInbox } from "@opencode-ai/core/session/inbox"
+import { SessionMessage } from "@opencode-ai/core/session/message"
+import { it } from "../lib/effect"
+import { host } from "./host"
+
+const sessionID = Session.ID.make("ses_plan_test")
+const plan = Agent.ID.make("plan")
+const build = Agent.ID.make("build")
+
+const agentSelected = (agent: Agent.ID, previous: Agent.ID): SessionEvent.AgentSelected => ({
+  id: Event.ID.create(),
+  created: 0,
+  durable: { aggregateID: sessionID, seq: Event.Seq.make(0), version: Event.Version.make(1) },
+  type: "session.agent.selected",
+  data: { sessionID, agent, previous },
+})
+
+/** Runs the plan plugin against stubbed domains, capturing persisted reminders and the context hook. */
+const run = Effect.fnUntraced(function* (events: ReadonlyArray<SessionEvent.AgentSelected> = []) {
+  const persisted = new Array<string>()
+  let contextHook: ((input: SessionContext) => Effect.Effect<void>) | undefined
+  yield* PlanPlugin.Plugin.effect(
+    host({
+      agent: {
+        get: () => Effect.die("unused agent.get"),
+        list: () => Effect.die("unused agent.list"),
+        reload: () => Effect.die("unused agent.reload"),
+        transform: () => Effect.succeed({ dispose: Effect.void }),
+      },
+      tool: {
+        transform: () => Effect.die("unused tool.transform"),
+        hook: () => Effect.succeed({ dispose: Effect.void }),
+      },
+      event: {
+        subscribe: () => Stream.fromIterable(events),
+      },
+      session: {
+        hook: (name, callback) => {
+          if (name === "context") contextHook = callback as (input: SessionContext) => Effect.Effect<void>
+          return Effect.succeed({ dispose: Effect.void })
+        },
+        synthetic: (input) => {
+          persisted.push(input.text)
+          return Effect.succeed(
+            SessionInbox.Synthetic.make({
+              id: SessionMessage.ID.make("msg_plan_test"),
+              sessionID,
+              timeCreated: DateTime.makeUnsafe(0),
+              type: "synthetic",
+              payload: { text: input.text },
+              delivery: "steer",
+            }),
+          )
+        },
+      },
+    }),
+  )
+  if (!contextHook) return yield* Effect.die("plan plugin did not register a context hook")
+  return { persisted, contextHook }
+})
+
+const request = (agent: Agent.ID, messages: Array<Message>): SessionContext => ({
+  sessionID,
+  agent,
+  model: { id: Model.ID.make("test-model"), providerID: Provider.ID.make("test") },
+  system: [],
+  messages,
+  tools: {},
+})
+
+const settle = (persisted: ReadonlyArray<string>, expected: number, remaining = 1000): Effect.Effect<void, Error> =>
+  Effect.gen(function* () {
+    if (persisted.length >= expected) return
+    if (remaining === 0) {
+      return yield* Effect.fail(new Error(`Timed out waiting for ${expected} reminders, saw ${persisted.length}`))
+    }
+    yield* Effect.promise(() => Bun.sleep(1))
+    yield* settle(persisted, expected, remaining - 1)
+  })
+
+/** The exact reminder texts, derived from plugin behavior rather than duplicated here. */
+const reminders = Effect.gen(function* () {
+  const planRun = yield* run()
+  yield* planRun.contextHook(request(plan, []))
+  const buildRun = yield* run()
+  yield* buildRun.contextHook(request(build, [Message.user(planRun.persisted[0]!)]))
+  return { enter: planRun.persisted[0]!, leave: buildRun.persisted[0]! }
+})
+
+describe("plan plugin reminders", () => {
+  it.effect("injects enter and leave reminders on agent switches", () =>
+    Effect.gen(function* () {
+      const { persisted } = yield* run([agentSelected(plan, build), agentSelected(build, plan)])
+      yield* settle(persisted, 2)
+      expect(persisted[0]).toContain("You are in Plan mode")
+      expect(persisted[1]).toContain("NO LONGER in Plan mode")
+    }),
+  )
+
+  it.effect("reconciles a missing enter reminder into the request and persists it", () =>
+    Effect.gen(function* () {
+      const { persisted, contextHook } = yield* run()
+      const messages = [Message.user("what agent are you?")]
+      yield* contextHook(request(plan, messages))
+      expect(messages).toHaveLength(2)
+      // Inserted before the user's prompt, matching where agent-switch reminders land.
+      const first = messages[0]?.content[0]
+      expect(first?.type === "text" && first.text).toContain("You are in Plan mode")
+      expect(persisted).toHaveLength(1)
+    }),
+  )
+
+  it.effect("does nothing when the transcript already has a live enter reminder", () =>
+    Effect.gen(function* () {
+      const { enter } = yield* reminders
+      const { persisted, contextHook } = yield* run()
+      const messages = [Message.user(enter), Message.user("hello")]
+      yield* contextHook(request(plan, messages))
+      expect(messages).toHaveLength(2)
+      expect(persisted).toHaveLength(0)
+    }),
+  )
+
+  it.effect("reconciles a stale enter reminder with a leave reminder", () =>
+    Effect.gen(function* () {
+      const { enter } = yield* reminders
+      const { persisted, contextHook } = yield* run()
+      const messages = [Message.user(enter), Message.user("ok implement it")]
+      yield* contextHook(request(build, messages))
+      expect(messages).toHaveLength(3)
+      const middle = messages[1]?.content[0]
+      expect(middle?.type === "text" && middle.text).toContain("NO LONGER in Plan mode")
+      expect(persisted).toHaveLength(1)
+    }),
+  )
+
+  it.effect("does nothing for non-plan sessions without plan history", () =>
+    Effect.gen(function* () {
+      const { persisted, contextHook } = yield* run()
+      const messages = [Message.user("hello")]
+      yield* contextHook(request(build, messages))
+      expect(messages).toHaveLength(1)
+      expect(persisted).toHaveLength(0)
+    }),
+  )
+
+  it.effect("does nothing when a leave reminder already follows the enter reminder", () =>
+    Effect.gen(function* () {
+      const { enter, leave } = yield* reminders
+      const { persisted, contextHook } = yield* run()
+      const messages = [Message.user(enter), Message.user(leave), Message.user("continue")]
+      yield* contextHook(request(build, messages))
+      expect(messages).toHaveLength(3)
+      expect(persisted).toHaveLength(0)
+    }),
+  )
+
+  it.effect("treats reminder text quoted inside a larger message as not live", () =>
+    Effect.gen(function* () {
+      const { enter } = yield* reminders
+      const { persisted, contextHook } = yield* run()
+      // Mirrors a compaction checkpoint quoting the reminder inside <recent-context>.
+      const messages = [Message.user(`<conversation-checkpoint>\n${enter}\n</conversation-checkpoint>`)]
+      yield* contextHook(request(plan, messages))
+      expect(messages).toHaveLength(2)
+      expect(persisted).toHaveLength(1)
+    }),
+  )
+})

packages/tui/src/context/local.tsx

@@ -10,6 +10,7 @@ import { useClient } from "./client"
 import { RGBA } from "@opentui/core"
 import { readJson, writeJsonAtomic } from "../util/persistence"
 import {
+  availableModelVariant,
   createModelPreferenceRepository,
   cycleModelVariant,
   modelPreferenceKey,
@@ -221,7 +222,14 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
         if (route.data.type === "session") return sessionSelection(route.data.sessionID)
         const model = newSessionModel()
         if (!model) return
-        return { ...model, variant: normalizeModelVariant(preferences.variant[modelPreferenceKey(model)]) }
+        const info = models()?.find((item) => item.providerID === model.providerID && item.id === model.modelID)
+        return {
+          ...model,
+          variant: availableModelVariant(
+            preferences.variant[modelPreferenceKey(model)],
+            info?.variants?.map((item) => item.id) ?? [],
+          ),
+        }
       })
 
       const currentModel = createMemo(() => {
@@ -262,13 +270,12 @@ export const { use: useLocal, provider: LocalProvider } = createSimpleContext({
         if (route.data.type === "session") {
           const sessionID = route.data.sessionID
           const current = sessionSelection(sessionID)
-          const preferred = normalizeModelVariant(
+          const preferred =
             current?.providerID === model.providerID && current.modelID === model.modelID
               ? current.variant
-              : preferences.variant[modelPreferenceKey(model)],
-          )
+              : preferences.variant[modelPreferenceKey(model)]
           const info = models()?.find((item) => item.providerID === model.providerID && item.id === model.modelID)
-          const variant = preferred && info?.variants?.some((item) => item.id === preferred) ? preferred : undefined
+          const variant = availableModelVariant(preferred, info?.variants?.map((item) => item.id) ?? [])
           setSessionDraft(sessionID, { ...model, variant })
           return true
         }

packages/tui/src/model-preference.ts

@@ -39,6 +39,11 @@ export function normalizeModelVariant(value: string | undefined) {
   return value === "default" ? undefined : value
 }
 
+export function availableModelVariant(value: string | undefined, variants: string[]) {
+  const variant = normalizeModelVariant(value)
+  return variant && variants.includes(variant) ? variant : undefined
+}
+
 export function modelPreferenceKey(model: ModelPreferenceModel) {
   return `${model.providerID}/${model.modelID}`
 }

packages/tui/test/model-preference.test.ts

@@ -1,6 +1,6 @@
 import { expect, test } from "bun:test"
 import path from "node:path"
-import { createModelPreferenceRepository, decodeModelPreference } from "../src/model-preference"
+import { availableModelVariant, createModelPreferenceRepository, decodeModelPreference } from "../src/model-preference"
 import { tmpdir } from "./fixture/fixture"
 
 test("repairs known model preferences and preserves unrelated fields", () => {
@@ -19,6 +19,12 @@ test("repairs known model preferences and preserves unrelated fields", () => {
   })
 })
 
+test("drops a saved variant that is no longer available", () => {
+  expect(availableModelVariant("medium", [])).toBeUndefined()
+  expect(availableModelVariant("medium", ["low", "high"])).toBeUndefined()
+  expect(availableModelVariant("medium", ["low", "medium", "high"])).toBe("medium")
+})
+
 test("atomically serializes patches and variant updates", async () => {
   await using tmp = await tmpdir()
   const file = path.join(tmp.path, "model.json")