---
title: "AWS Bedrock best practices"
answer: "AWS Bedrock exposes two API surfaces and Coolhand records them as separate sources: `bedrock` for the OpenAI-compatible Chat Completions format, and `bedrock_anthropic` for the native Anthropic Messages format. Which one you call changes the field shape Coolhand can capture, so pick one per workload and stay on it."
category: "Provider guides"
tags: ["bedrock","aws","anthropic","providers"]
published: 2026-08-30T13:57:51Z
updated: 2026-08-30T13:57:51Z
canonical_url: https://coolhandlabs.com/help/aws-bedrock-best-practices
index_url: https://coolhandlabs.com/help.md
---

# AWS Bedrock best practices

AWS Bedrock exposes two API surfaces and Coolhand records them as separate sources: `bedrock` for the OpenAI-compatible Chat Completions format, and `bedrock_anthropic` for the native Anthropic Messages format. Which one you call changes the field shape Coolhand can capture, so pick one per workload and stay on it.

Bedrock exposes two distinct API surfaces, each captured as a separate source in Coolhand:

| Source | Endpoint |
|--------|---------|
| `bedrock` | OpenAI-compatible Chat Completions format |
| `bedrock_anthropic` | Native Anthropic Messages API format |

---

## Model IDs use Bedrock naming — not provider model names

**`bedrock` (OpenAI-compatible):**
```
amazon.nova-pro-v1:0
amazon.nova-lite-v1:0
meta.llama3-70b-instruct-v1:0
amazon.titan-text-premier-v1:0
```

**`bedrock_anthropic` (native Anthropic):**
```
anthropic.claude-3-5-sonnet-20241022-v2:0
anthropic.claude-3-5-haiku-20241022-v1:0
anthropic.claude-sonnet-4-5-20250929-v1:0
```

The same underlying Claude model has a different identifier on `bedrock_anthropic` vs. direct `anthropic` logs. Cross-provider filtering by model requires awareness of this naming difference.

---

## System prompt (`bedrock_anthropic` only)

Same as [Anthropic Best Practices](https://coolhandlabs.com/help/anthropic-api-best-practices.md): the system prompt is a top-level `system` field, not a `role: "system"` message.

---

## Structured outputs

**`bedrock`:** Native structured outputs are GA on Bedrock as of February 2026 via `outputConfig.textFormat` / `response_format`. Support varies by model; check the [AWS documentation](https://docs.aws.amazon.com/bedrock/latest/userguide/model-parameters.html) for per-model availability.

**`bedrock_anthropic`:** Same as [Anthropic Best Practices](https://coolhandlabs.com/help/anthropic-api-best-practices.md) — native structured outputs supported on current models; tool use is the fallback for older models/SDKs.

---

## Caching

**`bedrock`:** Cached Input Tokens are captured when the model reports a cache hit. Cache Creation Tokens are not surfaced by this endpoint and will always be blank. TTL and invalidation are model-dependent and not uniformly documented by AWS for the OpenAI-compatible interface.

**`bedrock_anthropic`:** Same mechanics as [Anthropic Best Practices](https://coolhandlabs.com/help/anthropic-api-best-practices.md) — explicit `cache_control: { type: "ephemeral" }` markers, 5-minute TTL, ~1.25× write rate / ~0.1× read rate. Coolhand captures both **Cache Creation Tokens** and **Cached Input Tokens**.

---

## Batch processing

AWS Bedrock Batch Inference reads a JSONL input file from S3, processes the requests asynchronously, and writes results to an S3 output path. Supported on most Bedrock models, including Claude and Nova models on both API surfaces.

- Completion target: within 24 hours (specify `completion_window: "24h"` in the job request)
- Input and output stay in your AWS account (S3 buckets you control)
- **50% of on-demand pricing** on supported foundation models

Docs: https://docs.aws.amazon.com/bedrock/latest/userguide/batch-inference.html

---

## Non-standard token fields (`bedrock` only)

| Field | When present |
|-------|-------------|
| **Cached Input Tokens** | When model reports a cache hit |
| **Audio Input Tokens** | Multimodal requests with audio input |

---

## Extended thinking (`bedrock_anthropic` only)

Same as [Anthropic Best Practices](https://coolhandlabs.com/help/anthropic-api-best-practices.md): must be explicitly requested; may include `[redacted thinking]` blocks.

---

## Latency

**`bedrock`:** Wall-clock time from the collector, not server-side processing time. Includes network transit to AWS and Bedrock routing overhead.

**`bedrock_anthropic`:** Prefers the `x-envoy-upstream-service-time` response header (server-side processing time in ms) when present, and falls back to the collector's wall-clock duration. Same behavior as direct Anthropic logs. Cross-region inference adds additional routing latency when enabled.


---

Related:
- [Anthropic API best practices](https://coolhandlabs.com/help/anthropic-api-best-practices.md)
- [OpenRouter best practices](https://coolhandlabs.com/help/openrouter-best-practices.md)
- [Azure OpenAI best practices](https://coolhandlabs.com/help/azure-openai-best-practices.md)
- [OpenAI API best practices](https://coolhandlabs.com/help/openai-api-best-practices.md)

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