Anthropic
Configure Anthropic (Claude) as an LLM provider in agentgateway.
Before you begin
Install and set up an agentgateway proxy.Set up access to Anthropic
Get an API key to access the Anthropic API.
Save the API key in an environment variable.
export ANTHROPIC_API_KEY=<insert your API key>Create a Kubernetes secret to store your Anthropic API key.
kubectl apply -f- <<EOF apiVersion: v1 kind: Secret metadata: name: anthropic-secret namespace: agentgateway-system type: Opaque stringData: Authorization: $ANTHROPIC_API_KEY EOFCreate an AgentgatewayBackend resource to configure your LLM provider that references the Anthropic API key secret.
kubectl apply -f- <<EOF apiVersion: agentgateway.dev/v1alpha1 kind: AgentgatewayBackend metadata: name: anthropic namespace: agentgateway-system spec: ai: provider: anthropic: model: "claude-opus-4-6" policies: auth: secretRef: name: anthropic-secret EOFReview the following table to understand this configuration. For more information, see the API reference.
Setting Description ai.provider.anthropicDefine the LLM provider that you want to use. The example uses Anthropic. anthropic.modelThe model to use to generate responses. In this example, you use the claude-opus-4-6model.policies.authProvide the credentials to use to access the Anthropic API. The example refers to the secret that you previously created. The token is automatically sent in the x-api-keyheader.Create an HTTPRoute resource that routes incoming traffic to the AgentgatewayBackend. The following example sets up a route on the
/anthropicpath. Note that agentgateway automatically rewrites the endpoint to the Anthropic/v1/messagesendpoint.kubectl apply -f- <<EOF apiVersion: gateway.networking.k8s.io/v1 kind: HTTPRoute metadata: name: anthropic namespace: agentgateway-system spec: parentRefs: - name: agentgateway-proxy namespace: agentgateway-system rules: - backendRefs: - name: anthropic namespace: agentgateway-system group: agentgateway.dev kind: AgentgatewayBackend EOFkubectl apply -f- <<EOF apiVersion: gateway.networking.k8s.io/v1 kind: HTTPRoute metadata: name: anthropic namespace: agentgateway-system spec: parentRefs: - name: agentgateway-proxy namespace: agentgateway-system rules: - matches: - path: type: PathPrefix value: /v1/chat/completions backendRefs: - name: anthropic namespace: agentgateway-system group: agentgateway.dev kind: AgentgatewayBackend EOFkubectl apply -f- <<EOF apiVersion: gateway.networking.k8s.io/v1 kind: HTTPRoute metadata: name: anthropic namespace: agentgateway-system spec: parentRefs: - name: agentgateway-proxy namespace: agentgateway-system rules: - matches: - path: type: PathPrefix value: /anthropic backendRefs: - name: anthropic namespace: agentgateway-system group: agentgateway.dev kind: AgentgatewayBackend EOFSend a request to the LLM provider API along the route that you previously created. Verify that the request succeeds and that you get back a response from the API.
Cloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/messages" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqLocalhost:
curl "localhost:8080/v1/messages" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqCloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/chat/completions" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqLocalhost:
curl "localhost:8080/v1/chat/completions" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqCloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/anthropic" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqLocalhost:
curl "localhost:8080/anthropic" -H content-type:application/json -d '{ "model": "", "messages": [ { "role": "user", "content": "Explain how AI works in simple terms." } ] }' | jqExample output:
{ "model": "claude-opus-4-6", "usage": { "prompt_tokens": 16, "completion_tokens": 318, "total_tokens": 334 }, "choices": [ { "message": { "content": "Artificial Intelligence (AI) is a field of computer science that focuses on creating machines that can perform tasks that typically require human intelligence, such as visual perception, speech recognition, decision-making, and language translation. Here's a simple explanation of how AI works:\n\n1. Data input: AI systems require data to learn and make decisions. This data can be in the form of images, text, numbers, or any other format.\n\n2. Training: The AI system is trained using this data. During training, the system learns to recognize patterns, relationships, and make predictions based on the input data.\n\n3. Algorithms: AI uses various algorithms, which are sets of instructions or rules, to process and analyze the data. These algorithms can be simple or complex, depending on the task at hand.\n\n4. Machine Learning: A subset of AI, machine learning, enables the system to automatically learn and improve from experience without being explicitly programmed. As the AI system is exposed to more data, it can refine its algorithms and become more accurate over time.\n\n5. Output: Once the AI system has processed the data, it generates an output. This output can be a prediction, a decision, or an action, depending on the purpose of the AI system.\n\nAI can be categorized into narrow (weak) AI and general (strong) AI. Narrow AI is designed to perform a specific task, such as playing chess or recognizing speech, while general AI aims to have human-like intelligence that can perform any intellectual task.", "role": "assistant" }, "index": 0, "finish_reason": "stop" } ], "id": "msg_01PbaJfDHnjEBG4BueJNR2ff", "created": 1764627002, "object": "chat.completion" }
Extended thinking and reasoing
Extended thinking and reasoning lets Claude reason through complex problems before generating a response. You can opt in to extended thinking and reasoning by adding specific parameters to your request.
claude-opus-4-6.To opt in to extended thinking, include the thinking.type field in your request. You can also set the output_config.effort field to control how much reasoning the model applies.
The following values are supported:
thinking field
type value | Additional fields | Behavior |
|---|---|---|
adaptive | output_config.effort | The model decides whether to think and how much. Requires output_config.effort to be set. |
enabled | budget_tokens: <number> | Explicitly enables thinking with a fixed token budget. Works standalone without output_config. |
disabled | none | Explicitly disables thinking. |
output_config field
output_config has two independent sub-fields. You can use either or both.
| Sub-field | Description |
|---|---|
effort | Controls the reasoning effort level. Accepted values: low, medium, high, max. |
format | Constrains the response to a JSON schema. Set type to json_schema and provide a schema object. For more information, see Structured outputs. |
The following example request uses adaptive extended thinking. Note that this setting requires the output_config.effort field to be set too.
Cloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/messages" -H content-type:application/json -d '{
"model": "",
"max_tokens": 1024,
"thinking": {
"type": "adaptive"
},
"output_config": {
"effort": "high"
},
"messages": [
{
"role": "user",
"content": "Explain the trade-offs between consistency and availability in distributed systems."
}
]
}' | jqLocalhost:
curl "localhost:8080/v1/messages" -H content-type:application/json -d '{
"model": "",
"max_tokens": 1024,
"thinking": {
"type": "adaptive"
},
"output_config": {
"effort": "high"
},
"messages": [
{
"role": "user",
"content": "Explain the trade-offs between consistency and availability in distributed systems."
}
]
}' | jqExample output:
{
"id": "msg_01HVEzWf4NJrsKyVeEUDnHNW",
"type": "message",
"role": "assistant",
"model": "claude-opus-4-6",
"content": [
{
"type": "thinking",
"thinking": "Let me think through the trade-offs between consistency and availability..."
},
{
"type": "text",
"text": "# Consistency vs. Availability in Distributed Systems\n\n..."
}
],
"stop_reason": "end_turn",
"stop_sequence": null,
"usage": {
"input_tokens": 21,
"output_tokens": 1024
}
}
Use the reasoning_effort field in your request to enable extended thinking. The value that you set is automatically mapped to a specific thinking budget as shown in the following table.
reasoning_effort value | Thinking budget |
|---|---|
minimal or low | 1,024 tokens |
medium | 2,048 tokens |
high or xhigh | 4,096 tokens |
Note that the max_tokens value must be greater than the tokens in the thinking budget for the request to succeed.
Cloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/chat/completions" -H content-type:application/json -d '{
"model": "",
"max_tokens": 6000,
"reasoning_effort": "high",
"messages": [
{
"role": "user",
"content": "Explain the trade-offs between consistency and availability in distributed systems."
}
]
}' | jqLocalhost:
curl "localhost:8080/v1/chat/completions" -H content-type:application/json -d '{
"model": "",
"max_tokens": 6000,
"reasoning_effort": "high",
"messages": [
{
"role": "user",
"content": "Explain the trade-offs between consistency and availability in distributed systems."
}
]
}' | jqExample output:
{
"model": "claude-opus-4-6",
"usage": {
"prompt_tokens": 50,
"completion_tokens": 2549,
"total_tokens": 2599,
"prompt_tokens_details": {
"cached_tokens": 0
},
"cache_read_input_tokens": 0,
"cache_creation_input_tokens": 0
},
"choices": [
{
"message": {
"content": "# Consistency vs. Availability in Distributed ..."
},
"index": 0,
"finish_reason": "stop"
}
],
"id": "msg_01CVnXAQYeWkUjeaDceBRk3e",
"created": 1773251049,
"object": "chat.completion"
}
Structured outputs
Structured outputs constrain the model to respond with a specific JSON schema. You must provide the schema definition in your request.
Provide the JSON schema definition in the output_config.format field.
Cloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/messages" -H content-type:application/json -d '{
"model": "",
"max_tokens": 256,
"output_config": {
"format": {
"type": "json_schema",
"schema": {
"type": "object",
"properties": {
"answer": { "type": "string" },
"confidence": { "type": "number" }
},
"required": ["answer", "confidence"],
"additionalProperties": false
}
}
},
"messages": [
{
"role": "user",
"content": "Is the sky blue? Respond with your answer and a confidence score between 0 and 1."
}
]
}' | jqLocalhost:
curl "localhost:8080/v1/messages" -H content-type:application/json -d '{
"model": "",
"max_tokens": 256,
"output_config": {
"format": {
"type": "json_schema",
"schema": {
"type": "object",
"properties": {
"answer": { "type": "string" },
"confidence": { "type": "number" }
},
"required": ["answer", "confidence"],
"additionalProperties": false
}
}
},
"messages": [
{
"role": "user",
"content": "Is the sky blue? Respond with your answer and a confidence score between 0 and 1."
}
]
}' | jqExample output:
{
"id": "msg_01PsCxtLN1vftAKZgvWXhCan",
"type": "message",
"role": "assistant",
"model": "claude-opus-4-6",
"content": [
{
"type": "text",
"text": "{\"answer\":\"Yes, the sky is blue during clear daytime conditions.\",\"confidence\":0.98}"
}
],
"stop_reason": "end_turn",
"stop_sequence": null,
"usage": {
"input_tokens": 29,
"output_tokens": 28
}
}
Provide the schema definition in the response_format field.
Cloud Provider LoadBalancer:
curl "$INGRESS_GW_ADDRESS/v1/chat/completions" -H content-type:application/json -d '{
"model": "",
"response_format": {
"type": "json_schema",
"json_schema": {
"name": "answer_schema",
"schema": {
"type": "object",
"properties": {
"answer": { "type": "string" },
"confidence": { "type": "number" }
},
"required": ["answer", "confidence"],
"additionalProperties": false
}
}
},
"messages": [
{
"role": "user",
"content": "Is the sky blue? Respond with your answer and a confidence score between 0 and 1."
}
]
}' | jqLocalhost:
curl "localhost:8080/v1/chat/completions" -H content-type:application/json -d '{
"model": "",
"response_format": {
"type": "json_schema",
"json_schema": {
"name": "answer_schema",
"schema": {
"type": "object",
"properties": {
"answer": { "type": "string" },
"confidence": { "type": "number" }
},
"required": ["answer", "confidence"],
"additionalProperties": false
}
}
},
"messages": [
{
"role": "user",
"content": "Is the sky blue? Respond with your answer and a confidence score between 0 and 1."
}
]
}' | jqExample output:
{
"model": "claude-opus-4-6",
"usage": {
"prompt_tokens": 192,
"completion_tokens": 68,
"total_tokens": 260,
"prompt_tokens_details": {
"cached_tokens": 0
},
"cache_read_input_tokens": 0,
"cache_creation_input_tokens": 0
},
"choices": [
{
"message": {
"content": "{\"answer\":\"Yes, the sky is blue...",
"role": "assistant"
},
"index": 0,
"finish_reason": "stop"
}
],
"id": "msg_01BLohqXbvfZHQnnXxmviCcg",
"created": 1773251560,
"object": "chat.completion"
}
Connect to Claude Code
To route Claude Code CLI traffic through agentgateway, see the Claude Code integration guide. For a full tutorial with prompt guards and observability, see the Claude Code CLI proxy tutorial.