diff --git a/internal/config/config.go b/internal/config/config.go
index d63a34f73d5210c2542be8a598ef38cb06339bd9..1d1f38ac303fe14c221cd0e186ca493ac76e067a 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -75,6 +75,8 @@ type ProviderConfig struct {
 
 	// Extra headers to send with each request to the provider.
 	ExtraHeaders map[string]string `json:"extra_headers,omitempty"`
+	// Extra body
+	ExtraBody map[string]any `json:"extra_body,omitempty"`
 
 	// Used to pass extra parameters to the provider.
 	ExtraParams map[string]string `json:"-"`
diff --git a/internal/config/load.go b/internal/config/load.go
index e056847aeeda476e819439384a16e0e237b067e1..0dd0a5fda518a7ef34b0da42dc6b23d37d4430ca 100644
--- a/internal/config/load.go
+++ b/internal/config/load.go
@@ -141,6 +141,7 @@ func (c *Config) configureProviders(env env.Env, resolver VariableResolver, know
 			Type:         p.Type,
 			Disable:      config.Disable,
 			ExtraHeaders: config.ExtraHeaders,
+			ExtraBody:    config.ExtraBody,
 			ExtraParams:  make(map[string]string),
 			Models:       p.Models,
 		}
diff --git a/internal/llm/provider/anthropic.go b/internal/llm/provider/anthropic.go
index a65f0b752367ca7b2e62f9dd263a7dd6e5ce7a53..e8c980aeb3cc35a51071227093fac8e8cd3a4b0c 100644
--- a/internal/llm/provider/anthropic.go
+++ b/internal/llm/provider/anthropic.go
@@ -45,6 +45,12 @@ func createAnthropicClient(opts providerClientOptions, useBedrock bool) anthropi
 	if useBedrock {
 		anthropicClientOptions = append(anthropicClientOptions, bedrock.WithLoadDefaultConfig(context.Background()))
 	}
+	for _, header := range opts.extraHeaders {
+		anthropicClientOptions = append(anthropicClientOptions, option.WithHeaderAdd(header, opts.extraHeaders[header]))
+	}
+	for key, value := range opts.extraBody {
+		anthropicClientOptions = append(anthropicClientOptions, option.WithJSONSet(key, value))
+	}
 	return anthropic.NewClient(anthropicClientOptions...)
 }
 
diff --git a/internal/llm/provider/openai.go b/internal/llm/provider/openai.go
index 4afac2c70809d6c98e0aa35022c296c3d95ef05e..f55914520774e2fcf5e6283e22365f4ce3621dc1 100644
--- a/internal/llm/provider/openai.go
+++ b/internal/llm/provider/openai.go
@@ -44,10 +44,12 @@ func createOpenAIClient(opts providerClientOptions) openai.Client {
 		}
 	}
 
-	if opts.extraHeaders != nil {
-		for key, value := range opts.extraHeaders {
-			openaiClientOptions = append(openaiClientOptions, option.WithHeader(key, value))
-		}
+	for key, value := range opts.extraHeaders {
+		openaiClientOptions = append(openaiClientOptions, option.WithHeader(key, value))
+	}
+
+	for extraKey, extraValue := range opts.extraBody {
+		openaiClientOptions = append(openaiClientOptions, option.WithJSONSet(extraKey, extraValue))
 	}
 
 	return openai.NewClient(openaiClientOptions...)
diff --git a/internal/llm/provider/provider.go b/internal/llm/provider/provider.go
index 12dd09392942b0c00e7caa975deefffa994b47b8..412093334169b4c0d59fdd4f3f72b1e427651307 100644
--- a/internal/llm/provider/provider.go
+++ b/internal/llm/provider/provider.go
@@ -70,6 +70,7 @@ type providerClientOptions struct {
 	systemMessage string
 	maxTokens     int64
 	extraHeaders  map[string]string
+	extraBody     map[string]any
 	extraParams   map[string]string
 }
 
@@ -147,6 +148,7 @@ func NewProvider(cfg config.ProviderConfig, opts ...ProviderClientOption) (Provi
 		config:       cfg,
 		apiKey:       resolvedAPIKey,
 		extraHeaders: cfg.ExtraHeaders,
+		extraBody:    cfg.ExtraBody,
 		model: func(tp config.SelectedModelType) provider.Model {
 			return *config.Get().GetModelByType(tp)
 		},