diff --git a/docs/docs/calling-baml/client-registry.mdx b/docs/docs/calling-baml/client-registry.mdx
index f4b5f1a83..4f4ec644a 100644
--- a/docs/docs/calling-baml/client-registry.mdx
+++ b/docs/docs/calling-baml/client-registry.mdx
@@ -84,12 +84,38 @@ run
 </Tab>
 
 <Tab title="OpenAPI">
-Dynamic types are not yet supported when used via OpenAPI.
 
-Please let us know if you want this feature, either via [Discord] or [GitHub][openapi-feedback-github-issue].
+The API supports passing client registry as a field on `__baml_options__` in the request body.
+
+Example request body:
+
+```json
+{
+    "resume": "Vaibhav Gupta",
+    "__baml_options__": {
+        "client_registry": {
+            "clients": [
+                {
+                    "name": "OpenAI",
+                    "provider": "openai",
+                    "retry_policy": null,
+                    "options": {
+                        "model": "gpt-4o-mini",
+                        "api_key": "sk-..."
+                    }
+                }
+            ],
+            "primary": "OpenAI"
+        }
+    }
+}
+```
+
+```sh
+curl -X POST http://localhost:2024/call/ExtractResume \
+    -H 'Content-Type: application/json' -d @body.json
+```
 
-[Discord]: https://discord.gg/BTNBeXGuaS
-[openapi-feedback-github-issue]: https://github.com/BoundaryML/baml/issues/892
 </Tab>
 
 </Tabs>
diff --git a/engine/baml-runtime/src/cli/serve/mod.rs b/engine/baml-runtime/src/cli/serve/mod.rs
index 01699b047..36369a8fe 100644
--- a/engine/baml-runtime/src/cli/serve/mod.rs
+++ b/engine/baml-runtime/src/cli/serve/mod.rs
@@ -25,13 +25,15 @@ use axum_extra::{
 use baml_types::BamlValue;
 use core::pin::Pin;
 use futures::Stream;
+use serde::{Deserialize, Serialize};
 use serde_json::json;
 use std::{path::PathBuf, sync::Arc, task::Poll};
 use tokio::{net::TcpListener, sync::RwLock};
 use tokio_stream::StreamExt;
 
 use crate::{
-    internal::llm_client::LLMResponse, BamlRuntime, FunctionResult, RuntimeContextManager,
+    client_registry::ClientRegistry, internal::llm_client::LLMResponse, BamlRuntime,
+    FunctionResult, RuntimeContextManager,
 };
 
 #[derive(clap::Args, Clone, Debug)]
@@ -50,6 +52,11 @@ pub struct ServeArgs {
     no_version_check: bool,
 }
 
+#[derive(Serialize, Deserialize, Clone, Debug)]
+pub struct BamlOptions {
+    pub client_registry: Option<ClientRegistry>,
+}
+
 impl ServeArgs {
     pub fn run(&self) -> Result<()> {
         if !self.preview {
@@ -326,17 +333,23 @@ Tip: test that the server is up using `curl http://localhost:{}/_debug/ping`
         Ok(())
     }
 
-    async fn baml_call(self: Arc<Self>, b_fn: String, b_args: serde_json::Value) -> Response {
+    async fn baml_call(
+        self: Arc<Self>,
+        b_fn: String,
+        b_args: serde_json::Value,
+        b_options: Option<BamlOptions>,
+    ) -> Response {
         let args = match parse_args(&b_fn, b_args) {
             Ok(args) => args,
             Err(e) => return e.into_response(),
         };
 
         let ctx_mgr = RuntimeContextManager::new_from_env_vars(std::env::vars().collect(), None);
+        let client_registry = b_options.and_then(|options| options.client_registry);
 
         let locked = self.b.read().await;
         let (result, _trace_id) = locked
-            .call_function(b_fn, &args, &ctx_mgr, None, None)
+            .call_function(b_fn, &args, &ctx_mgr, None, client_registry.as_ref())
             .await;
 
         match result {
@@ -367,10 +380,27 @@ Tip: test that the server is up using `curl http://localhost:{}/_debug/ping`
         extract::Path(b_fn): extract::Path<String>,
         extract::Json(b_args): extract::Json<serde_json::Value>,
     ) -> Response {
-        self.baml_call(b_fn, b_args).await
+        let mut b_options = None;
+        if let Some(options_value) = b_args.get("__baml_options__") {
+            match serde_json::from_value::<BamlOptions>(options_value.clone()) {
+                Ok(opts) => b_options = Some(opts),
+                Err(_) => {
+                    return BamlError::InvalidArgument(
+                        "Failed to parse __baml_options__".to_string(),
+                    )
+                    .into_response()
+                }
+            }
+        }
+        self.baml_call(b_fn, b_args, b_options).await
     }
 
-    fn baml_stream(self: Arc<Self>, b_fn: String, b_args: serde_json::Value) -> Response {
+    fn baml_stream(
+        self: Arc<Self>,
+        b_fn: String,
+        b_args: serde_json::Value,
+        b_options: Option<BamlOptions>,
+    ) -> Response {
         let (sender, receiver) = tokio::sync::mpsc::unbounded_channel();
 
         let args = match parse_args(&b_fn, b_args) {
@@ -378,15 +408,19 @@ Tip: test that the server is up using `curl http://localhost:{}/_debug/ping`
             Err(e) => return e.into_response(),
         };
 
+        let client_registry = b_options.and_then(|options| options.client_registry);
+
         tokio::spawn(async move {
             let ctx_mgr =
                 RuntimeContextManager::new_from_env_vars(std::env::vars().collect(), None);
 
-            let result_stream = self
-                .b
-                .read()
-                .await
-                .stream_function(b_fn, &args, &ctx_mgr, None, None);
+            let result_stream = self.b.read().await.stream_function(
+                b_fn,
+                &args,
+                &ctx_mgr,
+                None,
+                client_registry.as_ref(),
+            );
 
             match result_stream {
                 Ok(mut result_stream) => {
@@ -457,7 +491,19 @@ Tip: test that the server is up using `curl http://localhost:{}/_debug/ping`
         extract::Path(path): extract::Path<String>,
         extract::Json(body): extract::Json<serde_json::Value>,
     ) -> Response {
-        self.baml_stream(path, body)
+        let mut b_options = None;
+        if let Some(options_value) = body.get("__baml_options__") {
+            match serde_json::from_value::<BamlOptions>(options_value.clone()) {
+                Ok(opts) => b_options = Some(opts),
+                Err(_) => {
+                    return BamlError::InvalidArgument(
+                        "Failed to parse __baml_options__".to_string(),
+                    )
+                    .into_response()
+                }
+            }
+        }
+        self.baml_stream(path, body, b_options)
     }
 }
 
diff --git a/engine/baml-runtime/src/client_registry/mod.rs b/engine/baml-runtime/src/client_registry/mod.rs
index 123f8bb53..d65cae1c9 100644
--- a/engine/baml-runtime/src/client_registry/mod.rs
+++ b/engine/baml-runtime/src/client_registry/mod.rs
@@ -4,7 +4,7 @@ use std::collections::HashMap;
 use std::sync::Arc;
 
 use baml_types::{BamlMap, BamlValue};
-use serde::Serialize;
+use serde::{Deserialize, Deserializer, Serialize};
 
 use crate::{internal::llm_client::llm_provider::LLMProvider, RuntimeContext};
 
@@ -16,7 +16,7 @@ pub enum PrimitiveClient {
     Vertex,
 }
 
-#[derive(Serialize, Clone)]
+#[derive(Serialize, Clone, Deserialize, Debug)]
 pub struct ClientProperty {
     pub name: String,
     pub provider: String,
@@ -24,8 +24,9 @@ pub struct ClientProperty {
     pub options: BamlMap<String, BamlValue>,
 }
 
-#[derive(Clone)]
+#[derive(Clone, Serialize, Deserialize, Debug)]
 pub struct ClientRegistry {
+    #[serde(deserialize_with = "deserialize_clients")]
     clients: HashMap<String, ClientProperty>,
     primary: Option<String>,
 }
@@ -60,3 +61,13 @@ impl ClientRegistry {
         Ok((self.primary.clone(), clients))
     }
 }
+
+fn deserialize_clients<'de, D>(deserializer: D) -> Result<HashMap<String, ClientProperty>, D::Error>
+where
+    D: Deserializer<'de>,
+{
+    Ok(Vec::deserialize(deserializer)?
+        .into_iter()
+        .map(|client: ClientProperty| (client.name.clone(), client))
+        .collect())
+}
diff --git a/engine/language_client_codegen/src/openapi.rs b/engine/language_client_codegen/src/openapi.rs
index 21486fdab..bf8ec15ef 100644
--- a/engine/language_client_codegen/src/openapi.rs
+++ b/engine/language_client_codegen/src/openapi.rs
@@ -21,7 +21,7 @@ impl LanguageFeatures for OpenApiLanguageFeatures {
 #
 #  Welcome to Baml! To use this generated code, please run the following:
 #
-#  $ openapi-generator generate -c openapi.yaml -g <language> -o <output_dir>
+#  $ openapi-generator generate -i openapi.yaml -g <language> -o <output_dir>
 #
 ###############################################################################
 
@@ -223,6 +223,55 @@ impl Serialize for OpenApiSchema<'_> {
                             ],
                         }),
                     ),
+                    (
+                        "BamlOptions",
+                        json!({
+                            "type": "object",
+                            "nullable": false,
+                            "properties": {
+                                "client_registry": {
+                                    "type": "object",
+                                    "nullable": false,
+                                    "properties": {
+                                        "clients": {
+                                            "type": "array",
+                                            "items": {
+                                                "$ref": "#/components/schemas/ClientProperty"
+                                            }
+                                        },
+                                        "primary": {
+                                            "type": "string",
+                                            "nullable": false
+                                        }
+                                    },
+                                    "required": ["clients"]
+                                }
+                            }
+                        })
+                    ),
+                    (
+                        "ClientProperty",
+                        json!({
+                            "type": "object",
+                            "properties": {
+                                "name": {
+                                    "type": "string"
+                                },
+                                "provider": {
+                                    "type": "string"
+                                },
+                                "retry_policy": {
+                                    "type": "string",
+                                    "nullable": false
+                                },
+                                "options": {
+                                    "type": "object",
+                                    "additionalProperties": true
+                                }
+                            },
+                            "required": ["name", "provider", "options"]
+                        })
+                    )
                 ]
                 .into_iter()
                 .chain(schemas.into_iter())
@@ -329,6 +378,32 @@ impl<'ir> TryFrom<Walker<'ir, &'ir Node<Function>>> for OpenApiMethodDef<'ir> {
 
     fn try_from(value: Walker<'ir, &'ir Node<Function>>) -> Result<Self> {
         let function_name = value.item.elem.name();
+        let mut properties: IndexMap<String, TypeSpecWithMeta> = value
+                        .item
+                        .elem
+                        .inputs()
+                        .iter()
+                        .map(|(name, t)| {
+                            Ok((
+                                name.to_string(),
+                                t.to_type_spec(value.db).context(format!(
+                                    "Failed to convert arg {name} (for function {function_name}) to OpenAPI type",
+                                ))?,
+                            ))
+                        })
+                        .collect::<Result<_>>()?;
+        properties.insert(
+            "__baml_options__".to_string(),
+            TypeSpecWithMeta {
+                meta: TypeMetadata {
+                    title: None,
+                    r#enum: None,
+                    r#const: None,
+                    nullable: true,
+                },
+                type_spec: TypeSpec::Ref { r#ref: "#/components/schemas/BamlOptions".into() }
+            }
+        );
         Ok(Self {
             function_name,
             request_body: TypeSpecWithMeta {
@@ -348,20 +423,7 @@ impl<'ir> TryFrom<Walker<'ir, &'ir Node<Function>>> for OpenApiMethodDef<'ir> {
                     nullable: false,
                 },
                 type_spec: TypeSpec::Inline(TypeDef::Class {
-                    properties: value
-                        .item
-                        .elem
-                        .inputs()
-                        .iter()
-                        .map(|(name, t)| {
-                            Ok((
-                                name.to_string(),
-                                t.to_type_spec(value.db).context(format!(
-                                    "Failed to convert arg {name} (for function {function_name}) to OpenAPI type",
-                                ))?,
-                            ))
-                        })
-                        .collect::<Result<_>>()?,
+                    properties,
                     required: value
                         .item
                         .elem
diff --git a/integ-tests/openapi/baml_client/.openapi-generator-ignore b/integ-tests/openapi/baml_client/.openapi-generator-ignore
index 90d8bf984..6a6064568 100644
--- a/integ-tests/openapi/baml_client/.openapi-generator-ignore
+++ b/integ-tests/openapi/baml_client/.openapi-generator-ignore
@@ -2,7 +2,7 @@
 #
 #  Welcome to Baml! To use this generated code, please run the following:
 #
-#  $ openapi-generator generate -c openapi.yaml -g <language> -o <output_dir>
+#  $ openapi-generator generate -i openapi.yaml -g <language> -o <output_dir>
 #
 ###############################################################################
 
diff --git a/integ-tests/openapi/baml_client/openapi.yaml b/integ-tests/openapi/baml_client/openapi.yaml
index d2261ec45..106c8afd8 100644
--- a/integ-tests/openapi/baml_client/openapi.yaml
+++ b/integ-tests/openapi/baml_client/openapi.yaml
@@ -2,7 +2,7 @@
 #
 #  Welcome to Baml! To use this generated code, please run the following:
 #
-#  $ openapi-generator generate -c openapi.yaml -g <language> -o <output_dir>
+#  $ openapi-generator generate -i openapi.yaml -g <language> -o <output_dir>
 #
 ###############################################################################
 
@@ -1070,6 +1070,9 @@ components:
             properties:
               recipe:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - recipe
             additionalProperties: false
@@ -1083,6 +1086,9 @@ components:
             properties:
               aud:
                 $ref: '#/components/schemas/BamlAudio'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - aud
             additionalProperties: false
@@ -1096,6 +1102,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1109,6 +1118,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1122,6 +1134,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1135,6 +1150,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1148,6 +1166,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1161,6 +1182,9 @@ components:
             properties:
               img:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - img
             additionalProperties: false
@@ -1176,6 +1200,9 @@ components:
                 $ref: '#/components/schemas/ClassWithImage'
               img2:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - classWithImage
             - img2
@@ -1192,6 +1219,9 @@ components:
                 $ref: '#/components/schemas/ClassWithImage'
               img2:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - classWithImage
             - img2
@@ -1208,6 +1238,9 @@ components:
                 $ref: '#/components/schemas/ClassWithImage'
               img2:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - classWithImage
             - img2
@@ -1222,6 +1255,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1235,6 +1271,9 @@ components:
             properties:
               input:
                 $ref: '#/components/schemas/DynamicClassOne'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1248,6 +1287,9 @@ components:
             properties:
               input:
                 $ref: '#/components/schemas/DynInputOutput'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1263,6 +1305,9 @@ components:
                 type: array
                 items:
                   $ref: '#/components/schemas/DynInputOutput'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1273,7 +1318,10 @@ components:
           schema:
             title: ExpectFailureRequest
             type: object
-            properties: {}
+            properties:
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required: []
             additionalProperties: false
     ExtractNames:
@@ -1286,6 +1334,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1299,6 +1350,9 @@ components:
             properties:
               text:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - text
             additionalProperties: false
@@ -1312,6 +1366,9 @@ components:
             properties:
               email:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - email
             additionalProperties: false
@@ -1327,6 +1384,9 @@ components:
                 type: string
               img:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - resume
             additionalProperties: false
@@ -1340,6 +1400,9 @@ components:
             properties:
               resume:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - resume
             additionalProperties: false
@@ -1353,6 +1416,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1366,6 +1432,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1379,6 +1448,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1392,6 +1464,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1405,6 +1480,9 @@ components:
             properties:
               myString:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required: []
             additionalProperties: false
     FnOutputBool:
@@ -1417,6 +1495,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1430,6 +1511,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1443,6 +1527,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1456,6 +1543,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1469,6 +1559,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1482,6 +1575,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1495,6 +1591,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1508,6 +1607,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1521,6 +1623,9 @@ components:
             properties:
               myArg:
                 $ref: '#/components/schemas/NamedArgsSingleEnum'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myArg
             additionalProperties: false
@@ -1534,6 +1639,9 @@ components:
             properties:
               text:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - text
             additionalProperties: false
@@ -1547,6 +1655,9 @@ components:
             properties:
               email:
                 $ref: '#/components/schemas/Email'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - email
             additionalProperties: false
@@ -1560,6 +1671,9 @@ components:
             properties:
               query:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - query
             additionalProperties: false
@@ -1573,6 +1687,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1586,6 +1703,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1599,6 +1719,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1612,6 +1735,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1625,6 +1751,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1638,6 +1767,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1651,6 +1783,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1664,6 +1799,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1677,6 +1815,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1690,6 +1831,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1703,6 +1847,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1716,6 +1863,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1729,6 +1879,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1742,6 +1895,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1755,6 +1911,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1765,7 +1924,10 @@ components:
           schema:
             title: TestFallbackClientRequest
             type: object
-            properties: {}
+            properties:
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required: []
             additionalProperties: false
     TestFallbackToShorthand:
@@ -1778,6 +1940,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1791,6 +1956,9 @@ components:
             properties:
               myBool:
                 type: boolean
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myBool
             additionalProperties: false
@@ -1804,6 +1972,9 @@ components:
             properties:
               myArg:
                 $ref: '#/components/schemas/NamedArgsSingleClass'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myArg
             additionalProperties: false
@@ -1819,6 +1990,9 @@ components:
                 type: array
                 items:
                   $ref: '#/components/schemas/NamedArgsSingleEnumList'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myArg
             additionalProperties: false
@@ -1832,6 +2006,9 @@ components:
             properties:
               myFloat:
                 type: number
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myFloat
             additionalProperties: false
@@ -1845,6 +2022,9 @@ components:
             properties:
               myInt:
                 type: integer
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myInt
             additionalProperties: false
@@ -1860,6 +2040,9 @@ components:
                 type: object
                 additionalProperties:
                   $ref: '#/components/schemas/StringToClassEntry'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myMap
             additionalProperties: false
@@ -1877,6 +2060,9 @@ components:
                   type: object
                   additionalProperties:
                     type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myMap
             additionalProperties: false
@@ -1892,6 +2078,9 @@ components:
                 type: object
                 additionalProperties:
                   type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myMap
             additionalProperties: false
@@ -1905,6 +2094,9 @@ components:
             properties:
               myString:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myString
             additionalProperties: false
@@ -1920,6 +2112,9 @@ components:
                 type: array
                 items:
                   type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myStringArray
             additionalProperties: false
@@ -1935,6 +2130,9 @@ components:
                 type: array
                 items:
                   type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myArg
             additionalProperties: false
@@ -1948,6 +2146,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -1961,6 +2162,9 @@ components:
             properties:
               img:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - img
             additionalProperties: false
@@ -1974,6 +2178,9 @@ components:
             properties:
               img:
                 $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - img
             additionalProperties: false
@@ -1989,6 +2196,9 @@ components:
                 type: array
                 items:
                   $ref: '#/components/schemas/BamlImage'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - imgs
             additionalProperties: false
@@ -2004,6 +2214,9 @@ components:
                 $ref: '#/components/schemas/NamedArgsSingleClass'
               myArg2:
                 $ref: '#/components/schemas/NamedArgsSingleClass'
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - myArg
             - myArg2
@@ -2018,6 +2231,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -2031,6 +2247,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -2044,6 +2263,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -2054,7 +2276,10 @@ components:
           schema:
             title: TestRetryConstantRequest
             type: object
-            properties: {}
+            properties:
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required: []
             additionalProperties: false
     TestRetryExponential:
@@ -2064,7 +2289,10 @@ components:
           schema:
             title: TestRetryExponentialRequest
             type: object
-            properties: {}
+            properties:
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required: []
             additionalProperties: false
     TestVertex:
@@ -2077,6 +2305,9 @@ components:
             properties:
               input:
                 type: string
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -2092,6 +2323,9 @@ components:
                 oneOf:
                 - type: string
                 - type: boolean
+              __baml_options__:
+                nullable: true
+                $ref: '#/components/schemas/BamlOptions'
             required:
             - input
             additionalProperties: false
@@ -2136,6 +2370,40 @@ components:
             type: string
         required:
         - url
+    BamlOptions:
+      type: object
+      nullable: false
+      properties:
+        client_registry:
+          type: object
+          nullable: false
+          properties:
+            clients:
+              type: array
+              items:
+                $ref: '#/components/schemas/ClientProperty'
+            primary:
+              type: string
+              nullable: false
+          required:
+          - clients
+    ClientProperty:
+      type: object
+      properties:
+        name:
+          type: string
+        provider:
+          type: string
+        retry_policy:
+          type: string
+          nullable: false
+        options:
+          type: object
+          additionalProperties: true
+      required:
+      - name
+      - provider
+      - options
     Category:
       enum:
       - Refund