refactor(look-at): split tools.ts to comply with 200 LOC module rule

Extract input preparation and image conversion handling into look-at-input-preparer.ts.

Extract prompt construction and multimodal session execution into look-at-prompt.ts and look-at-session-runner.ts while keeping createLookAt stable.

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/tools/look-at/look-at-input-preparer.ts

@@ -0,0 +1,154 @@
+import { basename } from "node:path"
+import { pathToFileURL } from "node:url"
+import type { LookAtArgs } from "./types"
+import {
+  extractBase64Data,
+  inferMimeTypeFromBase64,
+  inferMimeTypeFromFilePath,
+} from "./mime-type-inference"
+import {
+  needsConversion,
+  convertImageToJpeg,
+  convertBase64ImageToJpeg,
+  cleanupConvertedImage,
+} from "./image-converter"
+import { log } from "../../shared"
+
+export interface LookAtFilePart {
+  type: "file"
+  mime: string
+  url: string
+  filename: string
+}
+
+export interface PreparedLookAtInput {
+  readonly filePart: LookAtFilePart
+  readonly isBase64Input: boolean
+  readonly sourceDescription: string
+  cleanup(): void
+}
+
+type PrepareLookAtInputResult =
+  | { ok: true; value: PreparedLookAtInput }
+  | { ok: false; error: string }
+
+function getTemporaryConversionPath(error: unknown): string | null {
+  if (!(error instanceof Error)) {
+    return null
+  }
+
+  const temporaryOutputPath = Reflect.get(error, "temporaryOutputPath")
+  if (typeof temporaryOutputPath === "string" && temporaryOutputPath.length > 0) {
+    return temporaryOutputPath
+  }
+
+  const temporaryDirectory = Reflect.get(error, "temporaryDirectory")
+  if (typeof temporaryDirectory === "string" && temporaryDirectory.length > 0) {
+    return temporaryDirectory
+  }
+
+  return null
+}
+
+export function prepareLookAtInput(args: LookAtArgs): PrepareLookAtInputResult {
+  const imageData = args.image_data
+  const filePath = args.file_path
+
+  if (imageData) {
+    const mimeType = inferMimeTypeFromBase64(imageData)
+
+    let finalBase64Data = extractBase64Data(imageData)
+    let finalMimeType = mimeType
+    let tempFilesToCleanup: string[] = []
+
+    if (needsConversion(mimeType)) {
+      log(`[look_at] Detected unsupported Base64 format: ${mimeType}, converting to JPEG...`)
+      try {
+        const { base64, tempFiles } = convertBase64ImageToJpeg(finalBase64Data, mimeType)
+        finalBase64Data = base64
+        finalMimeType = "image/jpeg"
+        tempFilesToCleanup = tempFiles
+        log("[look_at] Base64 conversion successful")
+      } catch (conversionError) {
+        log(`[look_at] Base64 conversion failed: ${conversionError}`)
+        return {
+          ok: false,
+          error: `Error: Failed to convert Base64 image format. ${conversionError}`,
+        }
+      }
+    }
+
+    return {
+      ok: true,
+      value: {
+        isBase64Input: true,
+        sourceDescription: "clipboard/pasted image",
+        filePart: {
+          type: "file",
+          mime: finalMimeType,
+          url: `data:${finalMimeType};base64,${finalBase64Data}`,
+          filename: `clipboard-image.${finalMimeType.split("/")[1] || "png"}`,
+        },
+        cleanup() {
+          for (const temporaryFile of tempFilesToCleanup) {
+            cleanupConvertedImage(temporaryFile)
+          }
+        },
+      },
+    }
+  }
+
+  if (filePath) {
+    let mimeType = inferMimeTypeFromFilePath(filePath)
+    let actualFilePath = filePath
+    let tempFilePath: string | null = null
+    let tempConversionPath: string | null = null
+
+    if (needsConversion(mimeType)) {
+      log(`[look_at] Detected unsupported format: ${mimeType}, converting to JPEG...`)
+      try {
+        tempFilePath = convertImageToJpeg(filePath, mimeType)
+        tempConversionPath = tempFilePath
+        actualFilePath = tempFilePath
+        mimeType = "image/jpeg"
+        log(`[look_at] Conversion successful: ${tempFilePath}`)
+      } catch (conversionError) {
+        const failedConversionPath = getTemporaryConversionPath(conversionError)
+        if (failedConversionPath) {
+          tempConversionPath = failedConversionPath
+        }
+        log(`[look_at] Conversion failed: ${conversionError}`)
+        return {
+          ok: false,
+          error: `Error: Failed to convert image format. ${conversionError}`,
+        }
+      }
+    }
+
+    return {
+      ok: true,
+      value: {
+        isBase64Input: false,
+        sourceDescription: filePath,
+        filePart: {
+          type: "file",
+          mime: mimeType,
+          url: pathToFileURL(actualFilePath).href,
+          filename: basename(actualFilePath),
+        },
+        cleanup() {
+          if (tempConversionPath) {
+            cleanupConvertedImage(tempConversionPath)
+          } else if (tempFilePath) {
+            cleanupConvertedImage(tempFilePath)
+          }
+        },
+      },
+    }
+  }
+
+  return {
+    ok: false,
+    error: "Error: Must provide either 'file_path' or 'image_data'.",
+  }
+}

src/tools/look-at/look-at-prompt.ts

@@ -0,0 +1,18 @@
+export const READ_ENABLED = false
+
+export function buildLookAtPrompt(goal: string, isBase64Input: boolean): string {
+  const subjectNoun = isBase64Input ? "image" : "file"
+  const sourceClause = READ_ENABLED
+    ? "Use the Read tool on the provided file path to load its contents, then analyze it."
+    : `The ${subjectNoun} is already attached to this message. Analyze it directly from the attachment. Do NOT attempt to use the Read tool. The Read tool is disabled for this invocation and the ${subjectNoun} cannot be loaded by path.`
+
+  return `Analyze the attached ${subjectNoun} and extract the requested information.
+
+${sourceClause}
+
+Goal: ${goal}
+
+Provide ONLY the extracted information that matches the goal.
+Be thorough on what was requested, concise on everything else.
+If the requested information is not found, clearly state what is missing.`
+}

src/tools/look-at/look-at-session-runner.ts

@@ -0,0 +1,107 @@
+import type { PluginInput } from "@opencode-ai/plugin"
+import type { ToolContext } from "@opencode-ai/plugin/tool"
+import { log, promptSyncWithModelSuggestionRetry } from "../../shared"
+import { extractLatestAssistantText } from "./assistant-message-extractor"
+import { MULTIMODAL_LOOKER_AGENT } from "./constants"
+import { READ_ENABLED, buildLookAtPrompt } from "./look-at-prompt"
+import type { LookAtFilePart } from "./look-at-input-preparer"
+import { resolveMultimodalLookerAgentMetadata } from "./multimodal-agent-metadata"
+
+interface RunLookAtSessionInput {
+  ctx: PluginInput
+  toolContext: ToolContext
+  goal: string
+  filePart: LookAtFilePart
+  isBase64Input: boolean
+}
+
+export async function runLookAtSession({
+  ctx,
+  toolContext,
+  goal,
+  filePart,
+  isBase64Input,
+}: RunLookAtSessionInput): Promise<string> {
+  const prompt = buildLookAtPrompt(goal, isBase64Input)
+  const { agentModel, agentVariant } = await resolveMultimodalLookerAgentMetadata(ctx)
+
+  log(`[look_at] Creating session with parent: ${toolContext.sessionID}`)
+  const parentSession = await ctx.client.session.get({
+    path: { id: toolContext.sessionID },
+  }).catch(() => null)
+  const parentDirectory = parentSession?.data?.directory ?? ctx.directory
+
+  const createResult = await ctx.client.session.create({
+    body: {
+      parentID: toolContext.sessionID,
+      title: `look_at: ${goal.substring(0, 50)}`,
+    },
+    query: { directory: parentDirectory },
+  })
+
+  if (createResult.error) {
+    log("[look_at] Session create error:", createResult.error)
+    const errorString = String(createResult.error)
+    if (errorString.toLowerCase().includes("unauthorized")) {
+      return `Error: Failed to create session (Unauthorized). This may be due to:
+1. OAuth token restrictions (e.g., Claude Code credentials are restricted to Claude Code only)
+2. Provider authentication issues
+3. Session permission inheritance problems
+
+Try using a different provider or API key authentication.
+
+Original error: ${createResult.error}`
+    }
+
+    return `Error: Failed to create session: ${createResult.error}`
+  }
+
+  const sessionID = createResult.data.id
+  log(`[look_at] Created session: ${sessionID}`)
+
+  log(`[look_at] Sending prompt with ${isBase64Input ? "base64 image" : "file"} to session ${sessionID}`)
+  try {
+    await promptSyncWithModelSuggestionRetry(ctx.client, {
+      path: { id: sessionID },
+      body: {
+        agent: MULTIMODAL_LOOKER_AGENT,
+        tools: {
+          task: false,
+          call_omo_agent: false,
+          look_at: false,
+          read: READ_ENABLED,
+        },
+        parts: [
+          { type: "text", text: prompt },
+          filePart,
+        ],
+        ...(agentModel ? { model: { providerID: agentModel.providerID, modelID: agentModel.modelID } } : {}),
+        ...(agentVariant ? { variant: agentVariant } : {}),
+      },
+    })
+  } catch (promptError) {
+    log("[look_at] Prompt error (ignored, will still fetch messages):", promptError)
+  }
+
+  log(`[look_at] Fetching messages from session ${sessionID}...`)
+  const messagesResult = await ctx.client.session.messages({
+    path: { id: sessionID },
+  })
+
+  if (messagesResult.error) {
+    log("[look_at] Messages error:", messagesResult.error)
+    return `Error: Failed to get messages: ${messagesResult.error}`
+  }
+
+  const messages = messagesResult.data
+  log(`[look_at] Got ${messages.length} messages`)
+
+  const responseText = extractLatestAssistantText(messages)
+  if (!responseText) {
+    log("[look_at] No assistant message found")
+    return "Error: No response from multimodal-looker agent"
+  }
+
+  log(`[look_at] Got response, length: ${responseText.length}`)
+  return responseText
+}

src/tools/look-at/tools.ts

@@ -1,43 +1,11 @@
-import { basename } from "node:path"
-import { pathToFileURL } from "node:url"
 import { tool, type PluginInput, type ToolDefinition } from "@opencode-ai/plugin"
-import { LOOK_AT_DESCRIPTION, MULTIMODAL_LOOKER_AGENT } from "./constants"
+import { LOOK_AT_DESCRIPTION } from "./constants"
 import type { LookAtArgs } from "./types"
-import { log, promptSyncWithModelSuggestionRetry } from "../../shared"
+import { log } from "../../shared"
-import { extractLatestAssistantText } from "./assistant-message-extractor"
 import type { LookAtArgsWithAlias } from "./look-at-arguments"
 import { normalizeArgs, validateArgs } from "./look-at-arguments"
-import {
+import { prepareLookAtInput } from "./look-at-input-preparer"
-  extractBase64Data,
+import { runLookAtSession } from "./look-at-session-runner"
-  inferMimeTypeFromBase64,
-  inferMimeTypeFromFilePath,
-} from "./mime-type-inference"
-import { resolveMultimodalLookerAgentMetadata } from "./multimodal-agent-metadata"
-import {
-  needsConversion,
-  convertImageToJpeg,
-  convertBase64ImageToJpeg,
-  cleanupConvertedImage,
-} from "./image-converter"
-
-function getTemporaryConversionPath(error: unknown): string | null {
-  if (!(error instanceof Error)) {
-    return null
-  }
-
-  const temporaryOutputPath = Reflect.get(error, "temporaryOutputPath")
-  if (typeof temporaryOutputPath === "string" && temporaryOutputPath.length > 0) {
-    return temporaryOutputPath
-  }
-
-  const temporaryDirectory = Reflect.get(error, "temporaryDirectory")
-  if (typeof temporaryDirectory === "string" && temporaryDirectory.length > 0) {
-    return temporaryDirectory
-  }
-
-  return null
-}
-
 
 export { normalizeArgs, validateArgs } from "./look-at-arguments"
 
@@ -57,188 +25,29 @@ export function createLookAt(ctx: PluginInput): ToolDefinition {
         return validationError
       }
 
-      const isBase64Input = Boolean(args.image_data)
+      const preparedInputResult = prepareLookAtInput(args)
-      const sourceDescription = isBase64Input ? "clipboard/pasted image" : args.file_path
+      if (!preparedInputResult.ok) {
+        return preparedInputResult.error
+      }
+
+      const preparedInput = preparedInputResult.value
+      const { isBase64Input, sourceDescription } = preparedInput
       log(`[look_at] Analyzing ${sourceDescription}, goal: ${args.goal}`)
 
-      const imageData = args.image_data
-      const filePath = args.file_path
-
-      let mimeType: string
-      let filePart: { type: "file"; mime: string; url: string; filename: string }
-      let tempFilePath: string | null = null
-      let tempConversionPath: string | null = null
-      let tempFilesToCleanup: string[] = []
-
       try {
-        if (imageData) {
+        return await runLookAtSession({
-          mimeType = inferMimeTypeFromBase64(imageData)
+          ctx,
-          
+          toolContext,
-          let finalBase64Data = extractBase64Data(imageData)
+          goal: args.goal,
-          let finalMimeType = mimeType
+          filePart: preparedInput.filePart,
-          
+          isBase64Input,
-          if (needsConversion(mimeType)) {
-            log(`[look_at] Detected unsupported Base64 format: ${mimeType}, converting to JPEG...`)
-            try {
-              const { base64, tempFiles } = convertBase64ImageToJpeg(finalBase64Data, mimeType)
-              finalBase64Data = base64
-              finalMimeType = "image/jpeg"
-              tempFilesToCleanup = tempFiles
-              log(`[look_at] Base64 conversion successful`)
-            } catch (conversionError) {
-              log(`[look_at] Base64 conversion failed: ${conversionError}`)
-              return `Error: Failed to convert Base64 image format. ${conversionError}`
-            }
-          }
-          
-          filePart = {
-            type: "file",
-            mime: finalMimeType,
-            url: `data:${finalMimeType};base64,${finalBase64Data}`,
-            filename: `clipboard-image.${finalMimeType.split("/")[1] || "png"}`,
-          }
-        } else if (filePath) {
-        mimeType = inferMimeTypeFromFilePath(filePath)
-        
-        let actualFilePath = filePath
-        if (needsConversion(mimeType)) {
-          log(`[look_at] Detected unsupported format: ${mimeType}, converting to JPEG...`)
-          try {
-            tempFilePath = convertImageToJpeg(filePath, mimeType)
-            tempConversionPath = tempFilePath
-            actualFilePath = tempFilePath
-            mimeType = "image/jpeg"
-            log(`[look_at] Conversion successful: ${tempFilePath}`)
-          } catch (conversionError) {
-            const failedConversionPath = getTemporaryConversionPath(conversionError)
-            if (failedConversionPath) {
-              tempConversionPath = failedConversionPath
-            }
-            log(`[look_at] Conversion failed: ${conversionError}`)
-            return `Error: Failed to convert image format. ${conversionError}`
-          }
-        }
-
-        filePart = {
-          type: "file",
-          mime: mimeType,
-          url: pathToFileURL(actualFilePath).href,
-          filename: basename(actualFilePath),
-        }
-      } else {
-        return "Error: Must provide either 'file_path' or 'image_data'."
-      }
-
-      const readEnabled = false
-      const subjectNoun = isBase64Input ? "image" : "file"
-      const sourceClause = readEnabled
-        ? `Use the Read tool on the provided file path to load its contents, then analyze it.`
-        : `The ${subjectNoun} is already attached to this message. Analyze it directly from the attachment. Do NOT attempt to use the Read tool. The Read tool is disabled for this invocation and the ${subjectNoun} cannot be loaded by path.`
-
-      const prompt = `Analyze the attached ${subjectNoun} and extract the requested information.
-
-${sourceClause}
-
-Goal: ${args.goal}
-
-Provide ONLY the extracted information that matches the goal.
-Be thorough on what was requested, concise on everything else.
-If the requested information is not found, clearly state what is missing.`
-
-      const { agentModel, agentVariant } = await resolveMultimodalLookerAgentMetadata(ctx)
-
-      log(`[look_at] Creating session with parent: ${toolContext.sessionID}`)
-      const parentSession = await ctx.client.session.get({
-        path: { id: toolContext.sessionID },
-      }).catch(() => null)
-      const parentDirectory = parentSession?.data?.directory ?? ctx.directory
-
-      const createResult = await ctx.client.session.create({
-        body: {
-          parentID: toolContext.sessionID,
-          title: `look_at: ${args.goal.substring(0, 50)}`,
-        },
-        query: { directory: parentDirectory },
-      })
-
-      if (createResult.error) {
-        log(`[look_at] Session create error:`, createResult.error)
-        const errorStr = String(createResult.error)
-        if (errorStr.toLowerCase().includes("unauthorized")) {
-          return `Error: Failed to create session (Unauthorized). This may be due to:
-1. OAuth token restrictions (e.g., Claude Code credentials are restricted to Claude Code only)
-2. Provider authentication issues
-3. Session permission inheritance problems
-
-Try using a different provider or API key authentication.
-
-Original error: ${createResult.error}`
-        }
-        return `Error: Failed to create session: ${createResult.error}`
-      }
-
-      const sessionID = createResult.data.id
-      log(`[look_at] Created session: ${sessionID}`)
-
-      log(`[look_at] Sending prompt with ${isBase64Input ? "base64 image" : "file"} to session ${sessionID}`)
-      try {
-        await promptSyncWithModelSuggestionRetry(ctx.client, {
-          path: { id: sessionID },
-          body: {
-            agent: MULTIMODAL_LOOKER_AGENT,
-            tools: {
-              task: false,
-              call_omo_agent: false,
-              look_at: false,
-              read: readEnabled,
-            },
-            parts: [
-              { type: "text", text: prompt },
-              filePart,
-            ],
-            ...(agentModel ? { model: { providerID: agentModel.providerID, modelID: agentModel.modelID } } : {}),
-            ...(agentVariant ? { variant: agentVariant } : {}),
-          },
         })
-      } catch (promptError) {
-        log(`[look_at] Prompt error (ignored, will still fetch messages):`, promptError)
-      }
-
-      log(`[look_at] Fetching messages from session ${sessionID}...`)
-
-      const messagesResult = await ctx.client.session.messages({
-        path: { id: sessionID },
-      })
-
-      if (messagesResult.error) {
-        log(`[look_at] Messages error:`, messagesResult.error)
-        return `Error: Failed to get messages: ${messagesResult.error}`
-      }
-
-      const messages = messagesResult.data
-      log(`[look_at] Got ${messages.length} messages`)
-
-      const responseText = extractLatestAssistantText(messages)
-      if (!responseText) {
-        log("[look_at] No assistant message found")
-        return "Error: No response from multimodal-looker agent"
-      }
-
-        log(`[look_at] Got response, length: ${responseText.length}`)
-        return responseText
       } catch (error) {
         const errorMessage = error instanceof Error ? error.message : String(error)
         log(`[look_at] Unexpected error analyzing ${sourceDescription}:`, error)
         return `Error: Failed to analyze ${sourceDescription}: ${errorMessage}`
       } finally {
-        if (tempConversionPath) {
+        preparedInput.cleanup()
-          cleanupConvertedImage(tempConversionPath)
-        } else if (tempFilePath) {
-          cleanupConvertedImage(tempFilePath)
-        }
-        tempFilesToCleanup.forEach(file => {
-          cleanupConvertedImage(file)
-        })
       }
     },
   })