diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6f6cf0a523a..d0bad2cd589 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -33,6 +33,7 @@ Docs: https://docs.openclaw.ai
 - Auto-reply/Sessions: remove auth-key labels from `/new` and `/reset` confirmation messages so session reset notices never expose API key prefixes or env-key labels in chat output. (#24384, #24409) Thanks @Clawborn.
 - Slack/Group policy: move Slack account `groupPolicy` defaulting to provider-level schema defaults so multi-account configs inherit top-level `channels.slack.groupPolicy` instead of silently overriding inheritance with per-account `allowlist`. (#17579) Thanks @ZetiMente.
 - Providers/Anthropic: skip `context-1m-*` beta injection for OAuth/subscription tokens (`sk-ant-oat-*`) while preserving OAuth-required betas, avoiding Anthropic 401 auth failures when `params.context1m` is enabled. (#10647, #20354) Thanks @ClumsyWizardHands and @dcruver.
+- Providers/Bedrock: disable prompt-cache retention for non-Anthropic Bedrock models so Nova/Mistral requests do not send unsupported cache metadata. (#20866) Thanks @pierreeurope.
 - Providers/OpenRouter: remove conflicting top-level `reasoning_effort` when injecting nested `reasoning.effort`, preventing OpenRouter 400 payload-validation failures for reasoning models. (#24120) thanks @tenequm.
 - Providers/Groq: avoid classifying Groq TPM limit errors as context overflow so throttling paths no longer trigger overflow recovery logic. (#16176) Thanks @dddabtc.
 - Gateway/WS: close repeated post-handshake `unauthorized role:*` request floods per connection and sample duplicate rejection logs, preventing a single misbehaving client from degrading gateway responsiveness. (#20168) Thanks @acy103, @vibecodooor, and @vincentkoc.
diff --git a/src/agents/pi-embedded-runner-extraparams.test.ts b/src/agents/pi-embedded-runner-extraparams.test.ts
index 433bd816d6b..68d7327c33e 100644
--- a/src/agents/pi-embedded-runner-extraparams.test.ts
+++ b/src/agents/pi-embedded-runner-extraparams.test.ts
@@ -151,6 +151,42 @@ describe("applyExtraParamsToAgent", () => {
     });
   });
 
+  it("disables prompt caching for non-Anthropic Bedrock models", () => {
+    const { calls, agent } = createOptionsCaptureAgent();
+
+    applyExtraParamsToAgent(agent, undefined, "amazon-bedrock", "amazon.nova-micro-v1");
+
+    const model = {
+      api: "openai-completions",
+      provider: "amazon-bedrock",
+      id: "amazon.nova-micro-v1",
+    } as Model<"openai-completions">;
+    const context: Context = { messages: [] };
+
+    void agent.streamFn?.(model, context, {});
+
+    expect(calls).toHaveLength(1);
+    expect(calls[0]?.cacheRetention).toBe("none");
+  });
+
+  it("keeps Anthropic Bedrock models eligible for provider-side caching", () => {
+    const { calls, agent } = createOptionsCaptureAgent();
+
+    applyExtraParamsToAgent(agent, undefined, "amazon-bedrock", "us.anthropic.claude-sonnet-4-5");
+
+    const model = {
+      api: "openai-completions",
+      provider: "amazon-bedrock",
+      id: "us.anthropic.claude-sonnet-4-5",
+    } as Model<"openai-completions">;
+    const context: Context = { messages: [] };
+
+    void agent.streamFn?.(model, context, {});
+
+    expect(calls).toHaveLength(1);
+    expect(calls[0]?.cacheRetention).toBeUndefined();
+  });
+
   it("adds Anthropic 1M beta header when context1m is enabled for Opus/Sonnet", () => {
     const { calls, agent } = createOptionsCaptureAgent();
     const cfg = buildAnthropicModelConfig("anthropic/claude-opus-4-6", { context1m: true });
diff --git a/src/agents/pi-embedded-runner/extra-params.ts b/src/agents/pi-embedded-runner/extra-params.ts
index 3f69b5d5534..285ae6a5b23 100644
--- a/src/agents/pi-embedded-runner/extra-params.ts
+++ b/src/agents/pi-embedded-runner/extra-params.ts
@@ -137,6 +137,20 @@ function createStreamFnWithExtraParams(
   return wrappedStreamFn;
 }
 
+function isAnthropicBedrockModel(modelId: string): boolean {
+  const normalized = modelId.toLowerCase();
+  return normalized.includes("anthropic.claude") || normalized.includes("anthropic/claude");
+}
+
+function createBedrockNoCacheWrapper(baseStreamFn: StreamFn | undefined): StreamFn {
+  const underlying = baseStreamFn ?? streamSimple;
+  return (model, context, options) =>
+    underlying(model, context, {
+      ...options,
+      cacheRetention: "none",
+    });
+}
+
 function isDirectOpenAIBaseUrl(baseUrl: unknown): boolean {
   if (typeof baseUrl !== "string" || !baseUrl.trim()) {
     return true;
@@ -501,6 +515,11 @@ export function applyExtraParamsToAgent(
     agent.streamFn = createOpenRouterSystemCacheWrapper(agent.streamFn);
   }
 
+  if (provider === "amazon-bedrock" && !isAnthropicBedrockModel(modelId)) {
+    log.debug(`disabling prompt caching for non-Anthropic Bedrock model ${provider}/${modelId}`);
+    agent.streamFn = createBedrockNoCacheWrapper(agent.streamFn);
+  }
+
   // Enable Z.AI tool_stream for real-time tool call streaming.
   // Enabled by default for Z.AI provider, can be disabled via params.tool_stream: false
   if (provider === "zai" || provider === "z-ai") {