diff --git a/crates/Cargo.lock b/crates/Cargo.lock
index 8ce8097e..49c29f1b 100644
--- a/crates/Cargo.lock
+++ b/crates/Cargo.lock
@@ -1006,6 +1006,13 @@ version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"
 
+[[package]]
+name = "hermesllm"
+version = "0.1.0"
+dependencies = [
+ "common",
+]
+
 [[package]]
 name = "hermit-abi"
 version = "0.1.19"
diff --git a/crates/Cargo.toml b/crates/Cargo.toml
index 12eeb3b2..5cd6b29c 100644
--- a/crates/Cargo.toml
+++ b/crates/Cargo.toml
@@ -1,3 +1,3 @@
 [workspace]
 resolver = "2"
-members = ["llm_gateway", "prompt_gateway", "common", "brightstaff"]
+members = ["llm_gateway", "prompt_gateway", "common", "brightstaff", "hermesllm"]
diff --git a/crates/hermesllm/Cargo.toml b/crates/hermesllm/Cargo.toml
new file mode 100644
index 00000000..fdc60353
--- /dev/null
+++ b/crates/hermesllm/Cargo.toml
@@ -0,0 +1,7 @@
+[package]
+name = "hermesllm"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+common = { version = "0.1.0", path = "../common" }
diff --git a/crates/hermesllm/src/lib.rs b/crates/hermesllm/src/lib.rs
new file mode 100644
index 00000000..91283ab8
--- /dev/null
+++ b/crates/hermesllm/src/lib.rs
@@ -0,0 +1,145 @@
+//! hermesllm: A library for translating LLM API requests and responses
+//! between Mistral, Grok, Gemini, and OpenAI-compliant formats.
+
+/// Supported LLM providers.
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum Provider {
+    Mistral,
+    Grok,
+    Gemini,
+    OpenAI,
+}
+
+/// OpenAI API request format (placeholder).
+#[derive(Debug, Clone)]
+pub struct OpenAIRequest {
+    // Add OpenAI request fields here
+    pub prompt: String,
+    // ...
+}
+
+/// OpenAI API response format (placeholder).
+#[derive(Debug, Clone)]
+pub struct OpenAIResponse {
+    // Add OpenAI response fields here
+    pub completion: String,
+    // ...
+}
+
+/// Mistral API request format (placeholder).
+#[derive(Debug, Clone)]
+pub struct MistralRequest {
+    pub input: String,
+    // ...
+}
+
+/// Mistral API response format (placeholder).
+#[derive(Debug, Clone)]
+pub struct MistralResponse {
+    pub output: String,
+    // ...
+}
+
+/// Grok API request format (placeholder).
+#[derive(Debug, Clone)]
+pub struct GrokRequest {
+    pub message: String,
+    // ...
+}
+
+/// Grok API response format (placeholder).
+#[derive(Debug, Clone)]
+pub struct GrokResponse {
+    pub reply: String,
+    // ...
+}
+
+/// Gemini API request format (placeholder).
+#[derive(Debug, Clone)]
+pub struct GeminiRequest {
+    pub query: String,
+    // ...
+}
+
+/// Gemini API response format (placeholder).
+#[derive(Debug, Clone)]
+pub struct GeminiResponse {
+    pub answer: String,
+    // ...
+}
+
+/// Trait for translating provider-specific requests to OpenAI format.
+pub trait ToOpenAIRequest {
+    fn to_openai(&self) -> OpenAIRequest;
+}
+
+/// Trait for translating OpenAI responses to provider-specific format.
+pub trait FromOpenAIResponse: Sized {
+    fn from_openai(resp: &OpenAIResponse) -> Self;
+}
+
+// Implementations for Mistral
+impl ToOpenAIRequest for MistralRequest {
+    fn to_openai(&self) -> OpenAIRequest {
+        OpenAIRequest {
+            prompt: self.input.clone(),
+        }
+    }
+}
+impl FromOpenAIResponse for MistralResponse {
+    fn from_openai(resp: &OpenAIResponse) -> Self {
+        MistralResponse {
+            output: resp.completion.clone(),
+        }
+    }
+}
+
+// Implementations for Grok
+impl ToOpenAIRequest for GrokRequest {
+    fn to_openai(&self) -> OpenAIRequest {
+        OpenAIRequest {
+            prompt: self.message.clone(),
+        }
+    }
+}
+impl FromOpenAIResponse for GrokResponse {
+    fn from_openai(resp: &OpenAIResponse) -> Self {
+        GrokResponse {
+            reply: resp.completion.clone(),
+        }
+    }
+}
+
+// Implementations for Gemini
+impl ToOpenAIRequest for GeminiRequest {
+    fn to_openai(&self) -> OpenAIRequest {
+        OpenAIRequest {
+            prompt: self.query.clone(),
+        }
+    }
+}
+impl FromOpenAIResponse for GeminiResponse {
+    fn from_openai(resp: &OpenAIResponse) -> Self {
+        GeminiResponse {
+            answer: resp.completion.clone(),
+        }
+    }
+}
+
+// Optionally, add more conversion traits as needed for bidirectional translation.
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn mistral_to_openai_and_back() {
+        let mistral_req = MistralRequest { input: "Hello".into() };
+        let openai_req = mistral_req.to_openai();
+        assert_eq!(openai_req.prompt, "Hello");
+
+        let openai_resp = OpenAIResponse { completion: "Hi!".into() };
+        let mistral_resp = MistralResponse::from_openai(&openai_resp);
+        assert_eq!(mistral_resp.output, "Hi!");
+    }
+}