feat(agents): support Anthropic 1M context beta header

src/agents/pi-embedded-runner/extra-params.ts

@@ -8,6 +8,8 @@ const OPENROUTER_APP_HEADERS: Record<string, string> = {
   "HTTP-Referer": "https://openclaw.ai",
   "X-Title": "OpenClaw",
 };
+const ANTHROPIC_CONTEXT_1M_BETA = "context-1m-2025-08-07";
+const ANTHROPIC_1M_MODEL_PREFIXES = ["claude-opus-4", "claude-sonnet-4"] as const;
 // NOTE: We only force `store=true` for *direct* OpenAI Responses.
 // Codex responses (chatgpt.com/backend-api/codex/responses) require `store=false`.
 const OPENAI_RESPONSES_APIS = new Set(["openai-responses"]);
@@ -156,6 +158,78 @@ function createOpenAIResponsesStoreWrapper(baseStreamFn: StreamFn | undefined):
   };
 }
 
+function isAnthropic1MModel(modelId: string): boolean {
+  const normalized = modelId.trim().toLowerCase();
+  return ANTHROPIC_1M_MODEL_PREFIXES.some((prefix) => normalized.startsWith(prefix));
+}
+
+function parseHeaderList(value: unknown): string[] {
+  if (typeof value !== "string") {
+    return [];
+  }
+  return value
+    .split(",")
+    .map((item) => item.trim())
+    .filter(Boolean);
+}
+
+function resolveAnthropicBetas(
+  extraParams: Record<string, unknown> | undefined,
+  provider: string,
+  modelId: string,
+): string[] | undefined {
+  if (provider !== "anthropic") {
+    return undefined;
+  }
+
+  const betas = new Set<string>();
+  const configured = extraParams?.anthropicBeta;
+  if (typeof configured === "string" && configured.trim()) {
+    betas.add(configured.trim());
+  } else if (Array.isArray(configured)) {
+    for (const beta of configured) {
+      if (typeof beta === "string" && beta.trim()) {
+        betas.add(beta.trim());
+      }
+    }
+  }
+
+  if (extraParams?.context1m === true) {
+    if (isAnthropic1MModel(modelId)) {
+      betas.add(ANTHROPIC_CONTEXT_1M_BETA);
+    } else {
+      log.warn(`ignoring context1m for non-opus/sonnet model: ${provider}/${modelId}`);
+    }
+  }
+
+  return betas.size > 0 ? [...betas] : undefined;
+}
+
+function mergeAnthropicBetaHeader(
+  headers: Record<string, string> | undefined,
+  betas: string[],
+): Record<string, string> {
+  const merged = { ...headers };
+  const existingKey = Object.keys(merged).find((key) => key.toLowerCase() === "anthropic-beta");
+  const existing = existingKey ? parseHeaderList(merged[existingKey]) : [];
+  const values = Array.from(new Set([...existing, ...betas]));
+  const key = existingKey ?? "anthropic-beta";
+  merged[key] = values.join(",");
+  return merged;
+}
+
+function createAnthropicBetaHeadersWrapper(
+  baseStreamFn: StreamFn | undefined,
+  betas: string[],
+): StreamFn {
+  const underlying = baseStreamFn ?? streamSimple;
+  return (model, context, options) =>
+    underlying(model, context, {
+      ...options,
+      headers: mergeAnthropicBetaHeader(options?.headers, betas),
+    });
+}
+
 /**
  * Create a streamFn wrapper that adds OpenRouter app attribution headers.
  * These headers allow OpenClaw to appear on OpenRouter's leaderboard.
@@ -237,6 +311,14 @@ export function applyExtraParamsToAgent(
     agent.streamFn = wrappedStreamFn;
   }
 
+  const anthropicBetas = resolveAnthropicBetas(merged, provider, modelId);
+  if (anthropicBetas?.length) {
+    log.debug(
+      `applying Anthropic beta header for ${provider}/${modelId}: ${anthropicBetas.join(",")}`,
+    );
+    agent.streamFn = createAnthropicBetaHeadersWrapper(agent.streamFn, anthropicBetas);
+  }
+
   if (provider === "openrouter") {
     log.debug(`applying OpenRouter app attribution headers for ${provider}/${modelId}`);
     agent.streamFn = createOpenRouterHeadersWrapper(agent.streamFn);