diff --git a/.review/pr-8274 b/.review/pr-8274
new file mode 160000
index 0000000000..e46929b8d8
--- /dev/null
+++ b/.review/pr-8274
@@ -0,0 +1 @@
+Subproject commit e46929b8d8add0cd3c412d69f8ac882c405a4ba9
diff --git a/src/api/providers/__tests__/anthropic.spec.ts b/src/api/providers/__tests__/anthropic.spec.ts
index 7b74c87dfc..1b8e30b9ca 100644
--- a/src/api/providers/__tests__/anthropic.spec.ts
+++ b/src/api/providers/__tests__/anthropic.spec.ts
@@ -265,13 +265,14 @@ describe("AnthropicHandler", () => {
 			expect(result.temperature).toBe(0)
 		})
 
-		it("should handle Claude 4.5 Sonnet model correctly", () => {
+		it("should handle Claude 4.5 Sonnet model correctly and convert ID to API format", () => {
 			const handler = new AnthropicHandler({
 				apiKey: "test-api-key",
 				apiModelId: "claude-4.5-sonnet",
 			})
 			const model = handler.getModel()
-			expect(model.id).toBe("claude-4.5-sonnet")
+			// The model ID should be converted to the format expected by Anthropic API
+			expect(model.id).toBe("claude-sonnet-4-5")
 			expect(model.info.maxTokens).toBe(64000)
 			expect(model.info.contextWindow).toBe(200000)
 			expect(model.info.supportsReasoningBudget).toBe(true)
diff --git a/src/api/providers/anthropic.ts b/src/api/providers/anthropic.ts
index 80ef572b5b..7dc0190545 100644
--- a/src/api/providers/anthropic.ts
+++ b/src/api/providers/anthropic.ts
@@ -45,15 +45,23 @@ export class AnthropicHandler extends BaseProvider implements SingleCompletionHa
 		const cacheControl: CacheControlEphemeral = { type: "ephemeral" }
 		let { id: modelId, betas = [], maxTokens, temperature, reasoning: thinking } = this.getModel()
 
+		// Store the original model ID for switch statements
+		const originalModelId = modelId
+
+		// Convert claude-4.5-sonnet to the format expected by Anthropic API
+		if (modelId === "claude-4.5-sonnet") {
+			modelId = "claude-sonnet-4-5" as any
+		}
+
 		// Add 1M context beta flag if enabled for Claude Sonnet 4 and 4.5
 		if (
-			(modelId === "claude-sonnet-4-20250514" || modelId === "claude-4.5-sonnet") &&
+			(originalModelId === "claude-sonnet-4-20250514" || originalModelId === "claude-4.5-sonnet") &&
 			this.options.anthropicBeta1MContext
 		) {
 			betas.push("context-1m-2025-08-07")
 		}
 
-		switch (modelId) {
+		switch (originalModelId) {
 			case "claude-4.5-sonnet":
 			case "claude-sonnet-4-20250514":
 			case "claude-opus-4-1-20250805":
@@ -113,7 +121,7 @@ export class AnthropicHandler extends BaseProvider implements SingleCompletionHa
 						// https://github.com/anthropics/anthropic-sdk-typescript/commit/c920b77fc67bd839bfeb6716ceab9d7c9bbe7393
 
 						// Then check for models that support prompt caching
-						switch (modelId) {
+						switch (originalModelId) {
 							case "claude-4.5-sonnet":
 							case "claude-sonnet-4-20250514":
 							case "claude-opus-4-1-20250805":
@@ -275,8 +283,18 @@ export class AnthropicHandler extends BaseProvider implements SingleCompletionHa
 		// reasoning model and that reasoning is required to be enabled.
 		// The actual model ID honored by Anthropic's API does not have this
 		// suffix.
+
+		// Map internal model IDs to Anthropic API model IDs
+		let apiModelId = id
+		if (id === "claude-3-7-sonnet-20250219:thinking") {
+			apiModelId = "claude-3-7-sonnet-20250219"
+		} else if (id === "claude-4.5-sonnet") {
+			// Convert claude-4.5-sonnet to the format expected by Anthropic API
+			apiModelId = "claude-sonnet-4-5" as AnthropicModelId
+		}
+
 		return {
-			id: id === "claude-3-7-sonnet-20250219:thinking" ? "claude-3-7-sonnet-20250219" : id,
+			id: apiModelId,
 			info,
 			betas: id === "claude-3-7-sonnet-20250219:thinking" ? ["output-128k-2025-02-19"] : undefined,
 			...params,
diff --git a/tmp/pr-8287-Roo-Code b/tmp/pr-8287-Roo-Code
new file mode 160000
index 0000000000..88a473b017
--- /dev/null
+++ b/tmp/pr-8287-Roo-Code
@@ -0,0 +1 @@
+Subproject commit 88a473b017af37091c85ce3056e444e856f80d6e