refactor: reduce IBM watsonx provider bloat and improve code quality

- Reduce UI component from 470 to 313 lines (33% reduction)
- Remove redundant manual refresh button (follows LMStudio/Ollama pattern)
- Extract validation helper function to reduce duplication
- Consolidate duplicate credential input fields
- Fix region naming to use actual codes instead of pretty names
- Simplify handler variable declarations and error handling
- Remove redundant validation checks in fetcher
- Add documented constant for non-inference model filtering
- Overall 19% reduction across all watsonx files (913 -> 735 lines)

Author: daniel-lxs

packages/types/src/providers/ibm-watsonx.ts

@@ -10,6 +10,16 @@ export const REGION_TO_URL: Record<string, string> = {
 	"ap-south-1": "https://ap-south-1.aws.wxai.ibm.com",
 }
 
+/**
+ * Models that are not suitable for general text inference tasks.
+ * These are typically guard/safety models used for content moderation.
+ */
+export const WATSONX_NON_INFERENCE_MODELS = [
+	"meta-llama/llama-guard-3-11b-vision",
+	"ibm/granite-guardian-3-8b",
+	"ibm/granite-guardian-3-2b",
+] as const
+
 export type WatsonxAIModelId = keyof typeof watsonxModels
 export const watsonxDefaultModelId = "ibm/granite-3-3-8b-instruct"
 

src/api/providers/fetchers/ibm-watsonx.ts

@@ -1,4 +1,4 @@
-import { ModelInfo, REGION_TO_URL } from "@roo-code/types"
+import { ModelInfo, REGION_TO_URL, WATSONX_NON_INFERENCE_MODELS } from "@roo-code/types"
 import { IamAuthenticator, CloudPakForDataAuthenticator, UserOptions } from "ibm-cloud-sdk-core"
 import { WatsonXAI } from "@ibm-cloud/watsonx-ai"
 import WatsonxAiMlVml_v1 from "@ibm-cloud/watsonx-ai/dist/watsonx-ai-ml/vml_v1.js"
@@ -67,20 +67,18 @@ export async function getWatsonxModels(
 				throw new Error("Password is required for IBM Cloud Pak for Data")
 			}
 			options.serviceUrl = baseUrl
-			if (username) {
-				if (password) {
-					options.authenticator = new CloudPakForDataAuthenticator({
-						url: `${baseUrl}/icp4d-api`,
-						username: username,
-						password: password,
-					})
-				} else if (apiKey) {
-					options.authenticator = new CloudPakForDataAuthenticator({
-						url: `${baseUrl}/icp4d-api`,
-						username: username,
-						apikey: apiKey,
-					})
-				}
+			if (password) {
+				options.authenticator = new CloudPakForDataAuthenticator({
+					url: `${baseUrl}/icp4d-api`,
+					username,
+					password,
+				})
+			} else {
+				options.authenticator = new CloudPakForDataAuthenticator({
+					url: `${baseUrl}/icp4d-api`,
+					username,
+					apikey: apiKey,
+				})
 			}
 		}
 
@@ -96,39 +94,21 @@ export async function getWatsonxModels(
 				if (Array.isArray(modelsList) && modelsList.length > 0) {
 					for (const model of modelsList) {
 						const modelId = model.model_id
-						let contextWindow = 131072
-						if (model.model_limits && model.model_limits.max_sequence_length) {
-							contextWindow = model.model_limits.max_sequence_length
-						}
-						let maxTokens = Math.floor(contextWindow / 16)
-						if (
-							model.model_limits &&
-							model.training_parameters &&
-							model.training_parameters.max_output_tokens &&
-							model.training_parameters.max_output_tokens.max
-						) {
-							maxTokens = model.training_parameters.max_output_tokens.max
-						}
 
-						let description = ""
-						if (model.long_description) {
-							description = model.long_description
-						} else if (model.short_description) {
-							description = model.short_description
+						if (WATSONX_NON_INFERENCE_MODELS.includes(modelId as any)) {
+							continue
 						}
-						if (
-							!(
-								modelId === "meta-llama/llama-guard-3-11b-vision" ||
-								modelId === "ibm/granite-guardian-3-8b" ||
-								modelId === "ibm/granite-guardian-3-2b"
-							)
-						) {
-							knownModels[modelId] = {
-								contextWindow,
-								maxTokens,
-								supportsPromptCache: false,
-								description,
-							}
+
+						const contextWindow = model.model_limits?.max_sequence_length || 131072
+						const maxTokens =
+							model.training_parameters?.max_output_tokens?.max || Math.floor(contextWindow / 16)
+						const description = model.long_description || model.short_description || ""
+
+						knownModels[modelId] = {
+							contextWindow,
+							maxTokens,
+							supportsPromptCache: false,
+							description,
 						}
 					}
 				}

src/api/providers/ibm-watsonx.ts

@@ -148,32 +148,23 @@ export class WatsonxAIHandler extends BaseProvider implements SingleCompletionHa
 			const watsonxMessages = [{ role: "system", content: systemPrompt }, ...convertToOpenAiMessages(messages)]
 
 			const params = this.createTextChatParams(this.projectId!, modelId, watsonxMessages)
-			let responseText = ""
 
-			// Call the IBM watsonx API using textChat (non-streaming); can be changed to streaming..
 			const response = await this.service.textChat(params)
 
 			if (!response?.result?.choices?.[0]?.message?.content) {
 				throw new Error("Invalid or empty response from IBM watsonx API")
 			}
 
-			responseText = response.result.choices[0].message.content
+			const responseText = response.result.choices[0].message.content
 
 			yield {
 				type: "text",
 				text: responseText,
 			}
-			let usageInfo: WatsonXAI.TextChatUsage
-			usageInfo = response.result.usage || {}
 
-			let outputTokens = 0
-			if (usageInfo.completion_tokens) {
-				outputTokens = usageInfo.completion_tokens
-			} else {
-				console.error("[IBM watsonx] Failed to count output tokens:")
-			}
-
-			const inputTokens = usageInfo?.prompt_tokens || 0
+			const usageInfo = response.result.usage || {}
+			const inputTokens = usageInfo.prompt_tokens || 0
+			const outputTokens = usageInfo.completion_tokens || 0
 			const modelInfo = this.getModel().info
 			const totalCost = calculateApiCostOpenAI(modelInfo, inputTokens, outputTokens)
 
@@ -184,17 +175,18 @@ export class WatsonxAIHandler extends BaseProvider implements SingleCompletionHa
 				totalCost: totalCost,
 			}
 		} catch (error) {
-			// Extract error message and type from the error object
 			const errorMessage = error?.message || String(error)
 			const errorType = error?.type || undefined
+
 			let detailedMessage = errorMessage
 			if (errorMessage.includes("401") || errorMessage.includes("Unauthorized")) {
-				detailedMessage = `Authentication failed: ${errorMessage}. Please check your API key and credentials.`
+				detailedMessage = `Authentication failed. Please check your API key and credentials.`
 			} else if (errorMessage.includes("404")) {
-				detailedMessage = `Model or endpoint not found: ${errorMessage}. Please verify the model ID and base URL.`
+				detailedMessage = `Model or endpoint not found. Please verify the model ID and base URL.`
 			} else if (errorMessage.includes("timeout") || errorMessage.includes("ECONNREFUSED")) {
-				detailedMessage = `Connection failed: ${errorMessage}. Please check your network connection and base URL.`
+				detailedMessage = `Connection failed. Please check your network connection and base URL.`
 			}
+
 			yield {
 				type: "error",
 				error: errorType,