OpenAI responses streaming (#5837)

Co-authored-by: Michael Neale <michael.neale@gmail.com>
Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

crates/goose/src/providers/formats/mod.rs

@@ -4,4 +4,5 @@ pub mod databricks;
 pub mod gcpvertexai;
 pub mod google;
 pub mod openai;
+pub mod openai_responses;
 pub mod snowflake;

crates/goose/src/providers/formats/openai_responses.rs

@@ -0,0 +1,696 @@
+use crate::conversation::message::{Message, MessageContent};
+use crate::model::ModelConfig;
+use crate::providers::base::{ProviderUsage, Usage};
+use anyhow::{anyhow, Error};
+use async_stream::try_stream;
+use chrono;
+use futures::Stream;
+use rmcp::model::{object, CallToolRequestParam, RawContent, Role, Tool};
+use serde::{Deserialize, Serialize};
+use serde_json::{json, Value};
+use std::ops::Deref;
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ResponsesApiResponse {
+    pub id: String,
+    pub object: String,
+    pub created_at: i64,
+    pub status: String,
+    pub model: String,
+    pub output: Vec<ResponseOutputItem>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub reasoning: Option<ResponseReasoningInfo>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub usage: Option<ResponseUsage>,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(tag = "type")]
+#[serde(rename_all = "snake_case")]
+pub enum ResponseOutputItem {
+    Reasoning {
+        id: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        summary: Option<Vec<String>>,
+    },
+    Message {
+        id: String,
+        status: String,
+        role: String,
+        content: Vec<ResponseContentBlock>,
+    },
+    FunctionCall {
+        id: String,
+        status: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        call_id: Option<String>,
+        name: String,
+        arguments: String,
+    },
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(tag = "type")]
+#[serde(rename_all = "snake_case")]
+pub enum ResponseContentBlock {
+    OutputText {
+        text: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        annotations: Option<Vec<Value>>,
+    },
+    ToolCall {
+        id: String,
+        name: String,
+        input: Value,
+    },
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ResponseReasoningInfo {
+    pub effort: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub summary: Option<String>,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ResponseUsage {
+    pub input_tokens: i32,
+    pub output_tokens: i32,
+    pub total_tokens: i32,
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+#[serde(tag = "type")]
+#[serde(rename_all = "snake_case")]
+pub enum ResponsesStreamEvent {
+    #[serde(rename = "response.created")]
+    ResponseCreated {
+        sequence_number: i32,
+        response: ResponseMetadata,
+    },
+    #[serde(rename = "response.in_progress")]
+    ResponseInProgress {
+        sequence_number: i32,
+        response: ResponseMetadata,
+    },
+    #[serde(rename = "response.output_item.added")]
+    OutputItemAdded {
+        sequence_number: i32,
+        output_index: i32,
+        item: ResponseOutputItemInfo,
+    },
+    #[serde(rename = "response.content_part.added")]
+    ContentPartAdded {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        content_index: i32,
+        part: ContentPart,
+    },
+    #[serde(rename = "response.output_text.delta")]
+    OutputTextDelta {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        content_index: i32,
+        delta: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        logprobs: Option<Vec<Value>>,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        obfuscation: Option<String>,
+    },
+    #[serde(rename = "response.output_item.done")]
+    OutputItemDone {
+        sequence_number: i32,
+        output_index: i32,
+        item: ResponseOutputItemInfo,
+    },
+    #[serde(rename = "response.content_part.done")]
+    ContentPartDone {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        content_index: i32,
+        part: ContentPart,
+    },
+    #[serde(rename = "response.output_text.done")]
+    OutputTextDone {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        content_index: i32,
+        text: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        logprobs: Option<Vec<Value>>,
+    },
+    #[serde(rename = "response.completed")]
+    ResponseCompleted {
+        sequence_number: i32,
+        response: ResponseMetadata,
+    },
+    #[serde(rename = "response.failed")]
+    ResponseFailed { sequence_number: i32, error: Value },
+    #[serde(rename = "response.function_call_arguments.delta")]
+    FunctionCallArgumentsDelta {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        delta: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        obfuscation: Option<String>,
+    },
+    #[serde(rename = "response.function_call_arguments.done")]
+    FunctionCallArgumentsDone {
+        sequence_number: i32,
+        item_id: String,
+        output_index: i32,
+        arguments: String,
+    },
+    #[serde(rename = "error")]
+    Error { error: Value },
+}
+
+#[derive(Debug, Serialize, Deserialize)]
+pub struct ResponseMetadata {
+    pub id: String,
+    pub object: String,
+    pub created_at: i64,
+    pub status: String,
+    pub model: String,
+    pub output: Vec<ResponseOutputItemInfo>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub usage: Option<ResponseUsage>,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub reasoning: Option<ResponseReasoningInfo>,
+}
+
+#[derive(Debug, Serialize, Deserialize, Clone)]
+#[serde(tag = "type")]
+#[serde(rename_all = "snake_case")]
+pub enum ResponseOutputItemInfo {
+    Reasoning {
+        id: String,
+        summary: Vec<String>,
+    },
+    Message {
+        id: String,
+        status: String,
+        role: String,
+        content: Vec<ContentPart>,
+    },
+    FunctionCall {
+        id: String,
+        status: String,
+        call_id: String,
+        name: String,
+        arguments: String,
+    },
+}
+
+#[derive(Debug, Serialize, Deserialize, Clone)]
+#[serde(tag = "type")]
+#[serde(rename_all = "snake_case")]
+pub enum ContentPart {
+    OutputText {
+        text: String,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        annotations: Option<Vec<Value>>,
+        #[serde(skip_serializing_if = "Option::is_none")]
+        logprobs: Option<Vec<Value>>,
+    },
+    ToolCall {
+        id: String,
+        name: String,
+        arguments: String,
+    },
+}
+
+fn add_conversation_history(input_items: &mut Vec<Value>, messages: &[Message]) {
+    for message in messages.iter().filter(|m| m.is_agent_visible()) {
+        let has_only_tool_content = message.content.iter().all(|c| {
+            matches!(
+                c,
+                MessageContent::ToolRequest(_) | MessageContent::ToolResponse(_)
+            )
+        });
+
+        if has_only_tool_content {
+            continue;
+        }
+
+        if message.role != Role::User && message.role != Role::Assistant {
+            continue;
+        }
+
+        let role = match message.role {
+            Role::User => "user",
+            Role::Assistant => "assistant",
+        };
+
+        let mut content_items = Vec::new();
+        for content in &message.content {
+            if let MessageContent::Text(text) = content {
+                if !text.text.is_empty() {
+                    let content_type = if message.role == Role::Assistant {
+                        "output_text"
+                    } else {
+                        "input_text"
+                    };
+                    content_items.push(json!({
+                        "type": content_type,
+                        "text": text.text
+                    }));
+                }
+            }
+        }
+
+        if !content_items.is_empty() {
+            input_items.push(json!({
+                "role": role,
+                "content": content_items
+            }));
+        }
+    }
+}
+
+fn add_function_calls(input_items: &mut Vec<Value>, messages: &[Message]) {
+    for message in messages.iter().filter(|m| m.is_agent_visible()) {
+        if message.role == Role::Assistant {
+            for content in &message.content {
+                if let MessageContent::ToolRequest(request) = content {
+                    if let Ok(tool_call) = &request.tool_call {
+                        let arguments_str = tool_call
+                            .arguments
+                            .as_ref()
+                            .map(|args| {
+                                serde_json::to_string(args).unwrap_or_else(|_| "{}".to_string())
+                            })
+                            .unwrap_or_else(|| "{}".to_string());
+
+                        tracing::debug!(
+                            "Replaying function_call with call_id: {}, name: {}",
+                            request.id,
+                            tool_call.name
+                        );
+                        input_items.push(json!({
+                            "type": "function_call",
+                            "call_id": request.id,
+                            "name": tool_call.name,
+                            "arguments": arguments_str
+                        }));
+                    }
+                }
+            }
+        }
+    }
+}
+
+fn add_function_call_outputs(input_items: &mut Vec<Value>, messages: &[Message]) {
+    for message in messages.iter().filter(|m| m.is_agent_visible()) {
+        for content in &message.content {
+            if let MessageContent::ToolResponse(response) = content {
+                match &response.tool_result {
+                    Ok(contents) => {
+                        let text_content: Vec<String> = contents
+                            .content
+                            .iter()
+                            .filter_map(|c| {
+                                if let RawContent::Text(t) = c.deref() {
+                                    Some(t.text.clone())
+                                } else {
+                                    None
+                                }
+                            })
+                            .collect();
+
+                        if !text_content.is_empty() {
+                            tracing::debug!(
+                                "Sending function_call_output with call_id: {}",
+                                response.id
+                            );
+                            input_items.push(json!({
+                                "type": "function_call_output",
+                                "call_id": response.id,
+                                "output": text_content.join("\n")
+                            }));
+                        }
+                    }
+                    Err(error_data) => {
+                        // Handle error responses - must send them back to the API
+                        // to avoid "No tool output found" errors
+                        tracing::debug!(
+                            "Sending function_call_output error with call_id: {}",
+                            response.id
+                        );
+                        input_items.push(json!({
+                            "type": "function_call_output",
+                            "call_id": response.id,
+                            "output": format!("Error: {}", error_data.message)
+                        }));
+                    }
+                }
+            }
+        }
+    }
+}
+
+pub fn create_responses_request(
+    model_config: &ModelConfig,
+    system: &str,
+    messages: &[Message],
+    tools: &[Tool],
+) -> anyhow::Result<Value, Error> {
+    let mut input_items = Vec::new();
+
+    if !system.is_empty() {
+        input_items.push(json!({
+            "role": "system",
+            "content": [{
+                "type": "input_text",
+                "text": system
+            }]
+        }));
+    }
+
+    add_conversation_history(&mut input_items, messages);
+    add_function_calls(&mut input_items, messages);
+    add_function_call_outputs(&mut input_items, messages);
+
+    let mut payload = json!({
+        "model": model_config.model_name,
+        "input": input_items,
+        "store": false,  // Don't store responses on server (we replay history ourselves)
+    });
+
+    if !tools.is_empty() {
+        let tools_spec: Vec<Value> = tools
+            .iter()
+            .map(|tool| {
+                json!({
+                    "type": "function",
+                    "name": tool.name,
+                    "description": tool.description,
+                    "parameters": tool.input_schema,
+                })
+            })
+            .collect();
+
+        payload
+            .as_object_mut()
+            .unwrap()
+            .insert("tools".to_string(), json!(tools_spec));
+    }
+
+    if let Some(temp) = model_config.temperature {
+        payload
+            .as_object_mut()
+            .unwrap()
+            .insert("temperature".to_string(), json!(temp));
+    }
+
+    if let Some(tokens) = model_config.max_tokens {
+        payload
+            .as_object_mut()
+            .unwrap()
+            .insert("max_output_tokens".to_string(), json!(tokens));
+    }
+
+    Ok(payload)
+}
+
+pub fn responses_api_to_message(response: &ResponsesApiResponse) -> anyhow::Result<Message> {
+    let mut content = Vec::new();
+
+    for item in &response.output {
+        match item {
+            ResponseOutputItem::Reasoning { .. } => {
+                continue;
+            }
+            ResponseOutputItem::Message {
+                content: msg_content,
+                ..
+            } => {
+                for block in msg_content {
+                    match block {
+                        ResponseContentBlock::OutputText { text, .. } => {
+                            if !text.is_empty() {
+                                content.push(MessageContent::text(text));
+                            }
+                        }
+                        ResponseContentBlock::ToolCall { id, name, input } => {
+                            content.push(MessageContent::tool_request(
+                                id.clone(),
+                                Ok(CallToolRequestParam {
+                                    name: name.clone().into(),
+                                    arguments: Some(object(input.clone())),
+                                }),
+                            ));
+                        }
+                    }
+                }
+            }
+            ResponseOutputItem::FunctionCall {
+                id,
+                name,
+                arguments,
+                ..
+            } => {
+                tracing::debug!("Received FunctionCall with id: {}, name: {}", id, name);
+                let parsed_args = if arguments.is_empty() {
+                    json!({})
+                } else {
+                    serde_json::from_str(arguments).unwrap_or_else(|_| json!({}))
+                };
+
+                content.push(MessageContent::tool_request(
+                    id.clone(),
+                    Ok(CallToolRequestParam {
+                        name: name.clone().into(),
+                        arguments: Some(object(parsed_args)),
+                    }),
+                ));
+            }
+        }
+    }
+
+    let mut message = Message::new(Role::Assistant, chrono::Utc::now().timestamp(), content);
+
+    message = message.with_id(response.id.clone());
+
+    Ok(message)
+}
+
+pub fn get_responses_usage(response: &ResponsesApiResponse) -> Usage {
+    response.usage.as_ref().map_or_else(Usage::default, |u| {
+        Usage::new(
+            Some(u.input_tokens),
+            Some(u.output_tokens),
+            Some(u.total_tokens),
+        )
+    })
+}
+
+fn process_streaming_output_items(
+    output_items: Vec<ResponseOutputItemInfo>,
+    is_text_response: bool,
+) -> Vec<MessageContent> {
+    let mut content = Vec::new();
+
+    for item in output_items {
+        match item {
+            ResponseOutputItemInfo::Reasoning { .. } => {
+                // Skip reasoning items
+            }
+            ResponseOutputItemInfo::Message { content: parts, .. } => {
+                for part in parts {
+                    match part {
+                        ContentPart::OutputText { text, .. } => {
+                            if !text.is_empty() && !is_text_response {
+                                content.push(MessageContent::text(&text));
+                            }
+                        }
+                        ContentPart::ToolCall {
+                            id,
+                            name,
+                            arguments,
+                        } => {
+                            let parsed_args = if arguments.is_empty() {
+                                json!({})
+                            } else {
+                                serde_json::from_str(&arguments).unwrap_or_else(|_| json!({}))
+                            };
+
+                            content.push(MessageContent::tool_request(
+                                id,
+                                Ok(CallToolRequestParam {
+                                    name: name.into(),
+                                    arguments: Some(object(parsed_args)),
+                                }),
+                            ));
+                        }
+                    }
+                }
+            }
+            ResponseOutputItemInfo::FunctionCall {
+                call_id,
+                name,
+                arguments,
+                ..
+            } => {
+                let parsed_args = if arguments.is_empty() {
+                    json!({})
+                } else {
+                    serde_json::from_str(&arguments).unwrap_or_else(|_| json!({}))
+                };
+
+                content.push(MessageContent::tool_request(
+                    call_id,
+                    Ok(CallToolRequestParam {
+                        name: name.into(),
+                        arguments: Some(object(parsed_args)),
+                    }),
+                ));
+            }
+        }
+    }
+
+    content
+}
+
+pub fn responses_api_to_streaming_message<S>(
+    mut stream: S,
+) -> impl Stream<Item = anyhow::Result<(Option<Message>, Option<ProviderUsage>)>> + 'static
+where
+    S: Stream<Item = anyhow::Result<String>> + Unpin + Send + 'static,
+{
+    try_stream! {
+        use futures::StreamExt;
+
+        let mut accumulated_text = String::new();
+        let mut response_id: Option<String> = None;
+        let mut model_name: Option<String> = None;
+        let mut final_usage: Option<ProviderUsage> = None;
+        let mut output_items: Vec<ResponseOutputItemInfo> = Vec::new();
+        let mut is_text_response = false;
+
+        'outer: while let Some(response) = stream.next().await {
+            let response_str = response?;
+
+            // Skip empty lines
+            if response_str.trim().is_empty() {
+                continue;
+            }
+
+            // Parse SSE format: "event: <type>\ndata: <json>"
+            // For now, we only care about the data line
+            let data_line = if response_str.starts_with("data: ") {
+                response_str.strip_prefix("data: ").unwrap()
+            } else if response_str.starts_with("event: ") {
+                // Skip event type lines
+                continue;
+            } else {
+                // Try to parse as-is in case there's no prefix
+                &response_str
+            };
+
+            if data_line == "[DONE]" {
+                break 'outer;
+            }
+
+            let event: ResponsesStreamEvent = serde_json::from_str(data_line)
+                .map_err(|e| anyhow!("Failed to parse Responses stream event: {}: {:?}", e, data_line))?;
+
+            match event {
+                ResponsesStreamEvent::ResponseCreated { response, .. } |
+                ResponsesStreamEvent::ResponseInProgress { response, .. } => {
+                    response_id = Some(response.id);
+                    model_name = Some(response.model);
+                }
+
+                ResponsesStreamEvent::OutputTextDelta { delta, .. } => {
+                    is_text_response = true;
+                    accumulated_text.push_str(&delta);
+
+                    // Yield incremental text updates for true streaming
+                    let mut content = Vec::new();
+                    if !delta.is_empty() {
+                        content.push(MessageContent::text(&delta));
+                    }
+                    let mut msg = Message::new(Role::Assistant, chrono::Utc::now().timestamp(), content);
+
+                    // Add ID so desktop client knows these deltas are part of the same message
+                    if let Some(id) = &response_id {
+                        msg = msg.with_id(id.clone());
+                    }
+
+                    yield (Some(msg), None);
+                }
+
+                ResponsesStreamEvent::OutputItemDone { item, .. } => {
+                    output_items.push(item);
+                }
+
+                ResponsesStreamEvent::OutputTextDone { .. } => {
+                    // Text is already complete from deltas, this is just a summary event
+                }
+
+                ResponsesStreamEvent::ResponseCompleted { response, .. } => {
+                    let model = model_name.as_ref().unwrap_or(&response.model);
+                    let usage = response.usage.as_ref().map_or_else(
+                        Usage::default,
+                        |u| Usage::new(
+                            Some(u.input_tokens),
+                            Some(u.output_tokens),
+                            Some(u.total_tokens),
+                        ),
+                    );
+                    final_usage = Some(ProviderUsage {
+                        usage,
+                        model: model.clone(),
+                    });
+
+                    // For complete output, use the response output items
+                    if !response.output.is_empty() {
+                        output_items = response.output;
+                    }
+
+                    break 'outer;
+                }
+
+                ResponsesStreamEvent::FunctionCallArgumentsDelta { .. } => {
+                    // Function call arguments are being streamed, but we'll get the complete
+                    // arguments in the OutputItemDone event, so we can ignore deltas for now
+                }
+
+                ResponsesStreamEvent::FunctionCallArgumentsDone { .. } => {
+                    // Arguments are complete, will be in the OutputItemDone event
+                }
+
+                ResponsesStreamEvent::ResponseFailed { error, .. } => {
+                    Err(anyhow!("Responses API failed: {:?}", error))?;
+                }
+
+                ResponsesStreamEvent::Error { error } => {
+                    Err(anyhow!("Responses API error: {:?}", error))?;
+                }
+
+                _ => {
+                    // Ignore other event types (OutputItemAdded, ContentPartAdded, ContentPartDone)
+                }
+            }
+        }
+
+        // Process final output items and yield usage data
+        let content = process_streaming_output_items(output_items, is_text_response);
+
+        if !content.is_empty() {
+            let mut message = Message::new(Role::Assistant, chrono::Utc::now().timestamp(), content);
+            if let Some(id) = response_id {
+                message = message.with_id(id);
+            }
+            yield (Some(message), final_usage);
+        } else if let Some(usage) = final_usage {
+            yield (None, Some(usage));
+        }
+    }
+}

crates/goose/src/providers/openai.rs

@@ -15,7 +15,13 @@ use super::api_client::{ApiClient, AuthMethod};
 use super::base::{ConfigKey, ModelInfo, Provider, ProviderMetadata, ProviderUsage, Usage};
 use super::embedding::{EmbeddingCapable, EmbeddingRequest, EmbeddingResponse};
 use super::errors::ProviderError;
-use super::formats::openai::{create_request, get_usage, response_to_message};
+use super::formats::openai::{
+    create_request, get_usage, response_to_message, response_to_streaming_message,
+};
+use super::formats::openai_responses::{
+    create_responses_request, get_responses_usage, responses_api_to_message,
+    responses_api_to_streaming_message, ResponsesApiResponse,
+};
 use super::retry::ProviderRetry;
 use super::utils::{
     get_model, handle_response_openai_compat, handle_status_openai_compat, ImageFormat,
@@ -25,7 +31,6 @@ use crate::conversation::message::Message;
 
 use crate::model::ModelConfig;
 use crate::providers::base::MessageStream;
-use crate::providers::formats::openai::response_to_streaming_message;
 use crate::providers::utils::RequestLog;
 use rmcp::model::Tool;
 
@@ -41,6 +46,8 @@ pub const OPEN_AI_KNOWN_MODELS: &[(&str, usize)] = &[
     ("gpt-3.5-turbo", 16_385),
     ("gpt-4-turbo", 128_000),
     ("o4-mini", 128_000),
+    ("gpt-5.1-codex", 400_000),
+    ("gpt-5-codex", 400_000),
 ];
 
 pub const OPEN_AI_DOC_URL: &str = "https://platform.openai.com/docs/models";
@@ -184,6 +191,10 @@ impl OpenAiProvider {
         })
     }
 
+    fn uses_responses_api(model_name: &str) -> bool {
+        model_name.starts_with("gpt-5-codex") || model_name.starts_with("gpt-5.1-codex")
+    }
+
     async fn post(&self, payload: &Value) -> Result<Value, ProviderError> {
         let response = self
             .api_client
@@ -191,6 +202,14 @@ impl OpenAiProvider {
             .await?;
         handle_response_openai_compat(response).await
     }
+
+    async fn post_responses(&self, payload: &Value) -> Result<Value, ProviderError> {
+        let response = self
+            .api_client
+            .response_post("v1/responses", payload)
+            .await?;
+        handle_response_openai_compat(response).await
+    }
 }
 
 #[async_trait]
@@ -238,31 +257,62 @@ impl Provider for OpenAiProvider {
         messages: &[Message],
         tools: &[Tool],
     ) -> Result<(Message, ProviderUsage), ProviderError> {
-        let payload = create_request(model_config, system, messages, tools, &ImageFormat::OpenAi)?;
+        if Self::uses_responses_api(&model_config.model_name) {
+            let payload = create_responses_request(model_config, system, messages, tools)?;
+            let mut log = RequestLog::start(&self.model, &payload)?;
 
-        let mut log = RequestLog::start(&self.model, &payload)?;
-        let json_response = self
-            .with_retry(|| async {
-                let payload_clone = payload.clone();
-                self.post(&payload_clone).await
-            })
-            .await
-            .inspect_err(|e| {
-                let _ = log.error(e);
-            })?;
+            let json_response = self
+                .with_retry(|| async {
+                    let payload_clone = payload.clone();
+                    self.post_responses(&payload_clone).await
+                })
+                .await
+                .inspect_err(|e| {
+                    let _ = log.error(e);
+                })?;
 
-        let message = response_to_message(&json_response)?;
-        let usage = json_response
-            .get("usage")
-            .map(get_usage)
-            .unwrap_or_else(|| {
-                tracing::debug!("Failed to get usage data");
-                Usage::default()
-            });
+            let responses_api_response: ResponsesApiResponse =
+                serde_json::from_value(json_response.clone()).map_err(|e| {
+                    ProviderError::ExecutionError(format!(
+                        "Failed to parse responses API response: {}",
+                        e
+                    ))
+                })?;
 
-        let model = get_model(&json_response);
-        log.write(&json_response, Some(&usage))?;
-        Ok((message, ProviderUsage::new(model, usage)))
+            let message = responses_api_to_message(&responses_api_response)?;
+            let usage = get_responses_usage(&responses_api_response);
+            let model = responses_api_response.model.clone();
+
+            log.write(&json_response, Some(&usage))?;
+            Ok((message, ProviderUsage::new(model, usage)))
+        } else {
+            let payload =
+                create_request(model_config, system, messages, tools, &ImageFormat::OpenAi)?;
+
+            let mut log = RequestLog::start(&self.model, &payload)?;
+            let json_response = self
+                .with_retry(|| async {
+                    let payload_clone = payload.clone();
+                    self.post(&payload_clone).await
+                })
+                .await
+                .inspect_err(|e| {
+                    let _ = log.error(e);
+                })?;
+
+            let message = response_to_message(&json_response)?;
+            let usage = json_response
+                .get("usage")
+                .map(get_usage)
+                .unwrap_or_else(|| {
+                    tracing::debug!("Failed to get usage data");
+                    Usage::default()
+                });
+
+            let model = get_model(&json_response);
+            log.write(&json_response, Some(&usage))?;
+            Ok((message, ProviderUsage::new(model, usage)))
+        }
     }
 
     async fn fetch_supported_models(&self) -> Result<Option<Vec<String>>, ProviderError> {
@@ -319,40 +369,77 @@ impl Provider for OpenAiProvider {
         messages: &[Message],
         tools: &[Tool],
     ) -> Result<MessageStream, ProviderError> {
-        let mut payload =
-            create_request(&self.model, system, messages, tools, &ImageFormat::OpenAi)?;
-        payload["stream"] = serde_json::Value::Bool(true);
-        payload["stream_options"] = json!({
-            "include_usage": true,
-        });
-        let mut log = RequestLog::start(&self.model, &payload)?;
+        if Self::uses_responses_api(&self.model.model_name) {
+            let mut payload = create_responses_request(&self.model, system, messages, tools)?;
+            payload["stream"] = serde_json::Value::Bool(true);
 
-        let response = self
-            .with_retry(|| async {
-                let resp = self
-                    .api_client
-                    .response_post(&self.base_path, &payload)
-                    .await?;
-                handle_status_openai_compat(resp).await
-            })
-            .await
-            .inspect_err(|e| {
-                let _ = log.error(e);
-            })?;
-        let stream = response.bytes_stream().map_err(io::Error::other);
+            let mut log = RequestLog::start(&self.model, &payload)?;
 
-        Ok(Box::pin(try_stream! {
-            let stream_reader = StreamReader::new(stream);
-            let framed = FramedRead::new(stream_reader, LinesCodec::new()).map_err(anyhow::Error::from);
+            let response = self
+                .with_retry(|| async {
+                    let payload_clone = payload.clone();
+                    let resp = self
+                        .api_client
+                        .response_post("v1/responses", &payload_clone)
+                        .await?;
+                    handle_status_openai_compat(resp).await
+                })
+                .await
+                .inspect_err(|e| {
+                    let _ = log.error(e);
+                })?;
 
-            let message_stream = response_to_streaming_message(framed);
-            pin!(message_stream);
-            while let Some(message) = message_stream.next().await {
-                let (message, usage) = message.map_err(|e| ProviderError::RequestFailed(format!("Stream decode error: {}", e)))?;
-                log.write(&message, usage.as_ref().map(|f| f.usage).as_ref())?;
-                yield (message, usage);
-            }
-        }))
+            let stream = response.bytes_stream().map_err(io::Error::other);
+
+            Ok(Box::pin(try_stream! {
+                let stream_reader = StreamReader::new(stream);
+                let framed = FramedRead::new(stream_reader, LinesCodec::new()).map_err(anyhow::Error::from);
+
+                let message_stream = responses_api_to_streaming_message(framed);
+                pin!(message_stream);
+                while let Some(message) = message_stream.next().await {
+                    let (message, usage) = message.map_err(|e| ProviderError::RequestFailed(format!("Stream decode error: {}", e)))?;
+                    log.write(&message, usage.as_ref().map(|f| f.usage).as_ref())?;
+                    yield (message, usage);
+                }
+            }))
+        } else {
+            let mut payload =
+                create_request(&self.model, system, messages, tools, &ImageFormat::OpenAi)?;
+            payload["stream"] = serde_json::Value::Bool(true);
+            payload["stream_options"] = json!({
+                "include_usage": true,
+            });
+            let mut log = RequestLog::start(&self.model, &payload)?;
+
+            let response = self
+                .with_retry(|| async {
+                    let resp = self
+                        .api_client
+                        .response_post(&self.base_path, &payload)
+                        .await?;
+                    handle_status_openai_compat(resp).await
+                })
+                .await
+                .inspect_err(|e| {
+                    let _ = log.error(e);
+                })?;
+
+            let stream = response.bytes_stream().map_err(io::Error::other);
+
+            Ok(Box::pin(try_stream! {
+                let stream_reader = StreamReader::new(stream);
+                let framed = FramedRead::new(stream_reader, LinesCodec::new()).map_err(anyhow::Error::from);
+
+                let message_stream = response_to_streaming_message(framed);
+                pin!(message_stream);
+                while let Some(message) = message_stream.next().await {
+                    let (message, usage) = message.map_err(|e| ProviderError::RequestFailed(format!("Stream decode error: {}", e)))?;
+                    log.write(&message, usage.as_ref().map(|f| f.usage).as_ref())?;
+                    yield (message, usage);
+                }
+            }))
+        }
     }
 }