fix(core): restore webfetch image output

packages/core/src/tool/webfetch.ts

@@ -36,6 +36,14 @@ const Output = Schema.Struct({
   contentType: Schema.String,
   format: Input.fields.format,
   output: Schema.String,
+  data: Schema.String.pipe(Schema.optional),
+  mime: Schema.String.pipe(Schema.optional),
+})
+const StructuredOutput = Schema.Struct({
+  url: Output.fields.url,
+  contentType: Output.fields.contentType,
+  format: Output.fields.format,
+  output: Output.fields.output,
 })
 
 type Format = (typeof Input.Type)["format"]
@@ -104,7 +112,9 @@ const isTextualMime = (mime: string) =>
   mime === "application/xml" ||
   mime.endsWith("+xml") ||
   mime === "application/javascript" ||
-  mime === "application/x-javascript"
+  mime === "application/x-javascript" ||
+  mime === "image/svg+xml" ||
+  mime === "image/vnd.fastbidsheet"
 const convert = (content: string, contentType: string, format: Format) => {
   if (!contentType.includes("text/html")) return content
   if (format === "markdown") return convertHTMLToMarkdown(content)
@@ -126,7 +136,21 @@ export const Plugin = {
             description,
             input: Input,
             output: Output,
-            toModelOutput: ({ output }) => [{ type: "text", text: output.output }],
+            structured: StructuredOutput,
+            // Image base64 belongs in the native file content only so it is not persisted twice.
+            toStructuredOutput: ({ output }) => ({
+              url: output.url,
+              contentType: output.contentType,
+              format: output.format,
+              output: output.output,
+            }),
+            toModelOutput: ({ input, output }) => {
+              if (output.data === undefined || output.mime === undefined) return [{ type: "text", text: output.output }]
+              return [
+                { type: "text", text: output.output },
+                { type: "file", data: output.data, mime: output.mime, name: input.url },
+              ]
+            },
             execute: (input, context) =>
               Effect.gen(function* () {
                 yield* Effect.try({
@@ -150,9 +174,7 @@ export const Plugin = {
                   )
                   const contentType = response.headers["content-type"] || ""
                   const mime = mimeFrom(contentType)
-                  if (isImageAttachment(mime))
-                    return yield* Effect.fail(new Error(`Unsupported fetched image content type: ${mime}`))
-                  if (!isTextualMime(mime))
+                  if (!isTextualMime(mime) && !isImageAttachment(mime))
                     return yield* Effect.fail(new Error(`Unsupported fetched file content type: ${mime}`))
                   return { body: yield* collectBody(response), contentType }
                 }).pipe(
@@ -161,6 +183,16 @@ export const Plugin = {
                     orElse: () => Effect.fail(new Error("Request timed out")),
                   }),
                 )
+                const mime = mimeFrom(contentType)
+                if (isImageAttachment(mime))
+                  return {
+                    url: input.url,
+                    contentType,
+                    format: input.format,
+                    output: "Image fetched successfully",
+                    data: Buffer.from(body).toString("base64"),
+                    mime,
+                  }
                 const content = new TextDecoder().decode(body)
                 const output = yield* Effect.try({
                   try: () => convert(content, contentType, input.format),

packages/core/test/tool-webfetch.test.ts

@@ -234,14 +234,41 @@ describe("WebFetchTool registration", () => {
     }),
   )
 
-  it.effect("keeps images and files unsupported until typed settlement can carry attachments", () =>
+  it.effect("returns images as native media and keeps other files unsupported", () =>
     Effect.gen(function* () {
       reset()
       const registry = yield* ToolRegistry.Service
-      respond = () => Effect.succeed(new Response("png", { headers: { "content-type": "image/png" } }))
-      expect(yield* executeTool(registry, call({ url: "https://1.1.1.1/image", format: "html" }))).toEqual({
-        type: "error",
-        value: "Unable to fetch https://1.1.1.1/image",
+      respond = () => Effect.succeed(new Response("png", { headers: { "content-type": "IMAGE/PNG; charset=binary" } }))
+      expect(yield* settleTool(registry, call({ url: "https://1.1.1.1/image", format: "html" }))).toEqual({
+        result: {
+          type: "content",
+          value: [
+            { type: "text", text: "Image fetched successfully" },
+            {
+              type: "file",
+              uri: "data:image/png;base64,cG5n",
+              mime: "image/png",
+              name: "https://1.1.1.1/image",
+            },
+          ],
+        },
+        output: {
+          structured: {
+            url: "https://1.1.1.1/image",
+            contentType: "IMAGE/PNG; charset=binary",
+            format: "html",
+            output: "Image fetched successfully",
+          },
+          content: [
+            { type: "text", text: "Image fetched successfully" },
+            {
+              type: "file",
+              uri: "data:image/png;base64,cG5n",
+              mime: "image/png",
+              name: "https://1.1.1.1/image",
+            },
+          ],
+        },
       })
 
       respond = () => Effect.succeed(new Response("pdf", { headers: { "content-type": "application/pdf" } }))
@@ -252,6 +279,26 @@ describe("WebFetchTool registration", () => {
     }),
   )
 
+  it.effect("keeps SVG and FastBid sheets as text instead of image media", () =>
+    Effect.gen(function* () {
+      reset()
+      const registry = yield* ToolRegistry.Service
+      respond = () =>
+        Effect.succeed(new Response("<svg><text>hello</text></svg>", { headers: { "content-type": "image/svg+xml" } }))
+      expect(yield* executeTool(registry, call({ url: "https://1.1.1.1/image.svg", format: "html" }))).toEqual({
+        type: "text",
+        value: "<svg><text>hello</text></svg>",
+      })
+
+      respond = () =>
+        Effect.succeed(new Response("table Sheet {}", { headers: { "content-type": "image/vnd.fastbidsheet" } }))
+      expect(yield* executeTool(registry, call({ url: "https://1.1.1.1/sheet.fbs", format: "text" }))).toEqual({
+        type: "text",
+        value: "table Sheet {}",
+      })
+    }),
+  )
+
   it.effect("retries Cloudflare challenges with an honest user agent", () =>
     Effect.gen(function* () {
       reset()

packages/docs/attachments.mdx

@@ -17,6 +17,10 @@ and other binary prompt attachments are not currently included in the model
 request. Some clients may let you select a PDF, but V2 does not yet make that
 PDF visible to the model.
 
+The built-in `webfetch` tool returns HTTP image responses as image media when
+the response uses an `image/*` content type. SVG and FastBid sheet responses
+remain text.
+
 <Warning>
   Use a model that supports image input before attaching an image. OpenCode
   passes supported image media to the selected provider, but the provider and
@@ -133,9 +137,9 @@ All fields are optional:
 
 <Note>
   In the current V2 runtime, these settings apply to image media produced by
-  the built-in `read` tool. Images attached directly through the TUI, desktop,
-  web, CLI, or API bypass this normalization. Resize direct attachments before
-  adding them if the provider requires smaller media.
+  built-in tools such as `read` and `webfetch`. Images attached directly
+  through the TUI, desktop, web, CLI, or API bypass this normalization. Resize
+  direct attachments before adding them if the provider requires smaller media.
 </Note>
 
 The `read` tool recognizes PNG, JPEG, GIF, and WebP by their contents and will