diff --git a/packages/ai/CHANGELOG.md b/packages/ai/CHANGELOG.md
index ca22febb6..ecf7297f4 100644
--- a/packages/ai/CHANGELOG.md
+++ b/packages/ai/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Removed the `context-1m-2025-08-07` (1M long-context) beta from the Anthropic agent request headers, the OAuth model-discovery header, and the Claude usage-API header. Sending it caused subscription/OAuth requests without long-context credits to fail with `429 Usage credits are required for long context requests`, breaking Sonnet. The remaining betas are unchanged.
+
 ## [15.9.0] - 2026-06-04
 
 ### Fixed
diff --git a/packages/ai/src/provider-models/openai-compat.ts b/packages/ai/src/provider-models/openai-compat.ts
index c2b92702e..6111f001d 100644
--- a/packages/ai/src/provider-models/openai-compat.ts
+++ b/packages/ai/src/provider-models/openai-compat.ts
@@ -15,7 +15,7 @@ import { createBundledReferenceMap, createReferenceResolver } from "./bundled-re
 const MODELS_DEV_URL = "https://models.dev/api.json";
 const ANTHROPIC_BASE_URL = "https://api.anthropic.com/v1";
 const ANTHROPIC_OAUTH_BETA =
-	"claude-code-20250219,oauth-2025-04-20,context-1m-2025-08-07,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11";
+	"claude-code-20250219,oauth-2025-04-20,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11";
 
 export interface ModelsDevModel {
 	id?: string;
diff --git a/packages/ai/src/providers/anthropic.ts b/packages/ai/src/providers/anthropic.ts
index 81d6404b2..52c0c901e 100644
--- a/packages/ai/src/providers/anthropic.ts
+++ b/packages/ai/src/providers/anthropic.ts
@@ -132,7 +132,6 @@ const claudeCodeUtilityBetaDefaults = [
 const claudeCodeAgentBetaDefaults = [
 	"claude-code-20250219",
 	"oauth-2025-04-20",
-	"context-1m-2025-08-07",
 	"interleaved-thinking-2025-05-14",
 	"context-management-2025-06-27",
 	"prompt-caching-scope-2026-01-05",
diff --git a/packages/ai/src/usage/claude.ts b/packages/ai/src/usage/claude.ts
index b9e54c38a..1b4f389c1 100644
--- a/packages/ai/src/usage/claude.ts
+++ b/packages/ai/src/usage/claude.ts
@@ -22,7 +22,7 @@ const CLAUDE_HEADERS = {
 	accept: "application/json, text/plain, */*",
 	"accept-encoding": "gzip, compress, deflate, br",
 	"anthropic-beta":
-		"claude-code-20250219,oauth-2025-04-20,context-1m-2025-08-07,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
+		"claude-code-20250219,oauth-2025-04-20,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
 	"content-type": "application/json",
 	"user-agent": "claude-cli/2.1.160 (external, cli)",
 	connection: "keep-alive",
diff --git a/packages/ai/test/anthropic-alignment.test.ts b/packages/ai/test/anthropic-alignment.test.ts
index 8fa8bb3e1..b40a1b8b9 100644
--- a/packages/ai/test/anthropic-alignment.test.ts
+++ b/packages/ai/test/anthropic-alignment.test.ts
@@ -154,7 +154,7 @@ describe("Anthropic request fingerprint alignment", () => {
 		expect(headers["X-Claude-Code-Session-Id"]).toBe(sessionId);
 		expect(headers["x-client-request-id"]).toMatch(/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/);
 		expect(headers["Anthropic-Beta"]).toBe(
-			"claude-code-20250219,oauth-2025-04-20,context-1m-2025-08-07,interleaved-thinking-2025-05-14,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
+			"claude-code-20250219,oauth-2025-04-20,interleaved-thinking-2025-05-14,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
 		);
 	});
 
@@ -188,7 +188,7 @@ describe("Anthropic request fingerprint alignment", () => {
 
 		const hidden = buildAnthropicClientOptions({ ...baseArgs, thinkingDisplay: "omitted" });
 		expect(hidden.defaultHeaders["Anthropic-Beta"]).toBe(
-			"claude-code-20250219,oauth-2025-04-20,context-1m-2025-08-07,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
+			"claude-code-20250219,oauth-2025-04-20,interleaved-thinking-2025-05-14,redact-thinking-2026-02-12,context-management-2025-06-27,prompt-caching-scope-2026-01-05,mid-conversation-system-2026-04-07,advanced-tool-use-2025-11-20,effort-2025-11-24,extended-cache-ttl-2025-04-11",
 		);
 
 		const hiddenUtility = buildAnthropicClientOptions({
diff --git a/packages/ai/test/claude-usage-headers.test.ts b/packages/ai/test/claude-usage-headers.test.ts
index 1489726fd..a20dc6a1f 100644
--- a/packages/ai/test/claude-usage-headers.test.ts
+++ b/packages/ai/test/claude-usage-headers.test.ts
@@ -82,7 +82,6 @@ describe("claude usage request headers", () => {
 		const betaTokens = beta?.split(",").map(tokenValue => tokenValue.trim()) ?? [];
 		expect(betaTokens).toContain("claude-code-20250219");
 		expect(betaTokens).toContain("oauth-2025-04-20");
-		expect(betaTokens).toContain("context-1m-2025-08-07");
 		expect(betaTokens).toContain("interleaved-thinking-2025-05-14");
 		expect(betaTokens).toContain("redact-thinking-2026-02-12");
 		expect(betaTokens).toContain("context-management-2025-06-27");