diff --git a/src/api/errors.rs b/src/api/errors.rs
index a48025f..554a504 100644
--- a/src/api/errors.rs
+++ b/src/api/errors.rs
@@ -1,8 +1,16 @@
 use crate::databases::postgres::errors::DbError;
 use crate::providers::ollama::errors::OllamaError;
 
+use axum::Json;
 use axum::http::StatusCode;
 use axum::response::{IntoResponse, Response};
+use serde::Serialize;
+
+#[derive(Serialize)]
+pub struct ErrorResponse {
+    pub error: String,
+    pub code: String,
+}
 
 pub enum ApiError {
     Db(DbError),
@@ -23,44 +31,84 @@ impl From<OllamaError> for ApiError {
 
 impl IntoResponse for ApiError {
     fn into_response(self) -> Response {
-        let (status, msg) = match self {
+        let (status, body) = match self {
             ApiError::Db(db_err) => match db_err {
                 DbError::Connection(_) => (
                     StatusCode::INTERNAL_SERVER_ERROR,
-                    "database connection error".to_string(),
+                    ErrorResponse {
+                        error: "database connection error".to_string(),
+                        code: "DB_CONNECTION".to_string(),
+                    },
+                ),
+                DbError::Timeout => (
+                    StatusCode::REQUEST_TIMEOUT,
+                    ErrorResponse {
+                        error: "database timeout".to_string(),
+                        code: "DB_TIMEOUT".to_string(),
+                    },
+                ),
+                DbError::NotFound => (
+                    StatusCode::NOT_FOUND,
+                    ErrorResponse {
+                        error: "not found".to_string(),
+                        code: "DB_NOT_FOUND".to_string(),
+                    },
                 ),
-                DbError::Timeout => (StatusCode::REQUEST_TIMEOUT, "database timeout".to_string()),
-                DbError::NotFound => (StatusCode::NOT_FOUND, "not found".to_string()),
             },
 
-            ApiError::Ollama(ollama_err) => match ollama_err {
+            ApiError::Ollama(err) => match err {
                 OllamaError::MissingPrompt => (
                     StatusCode::BAD_REQUEST,
-                    "prompt is required and cannot be empty".to_string(),
+                    ErrorResponse {
+                        error: "prompt is required and cannot be empty".to_string(),
+                        code: "OLLAMA_MISSING_PROMPT".to_string(),
+                    },
                 ),
                 OllamaError::MissingModel => (
                     StatusCode::BAD_REQUEST,
-                    "model is required and cannot be empty".to_string(),
+                    ErrorResponse {
+                        error: "model is required and cannot be empty".to_string(),
+                        code: "OLLAMA_MISSING_MODEL".to_string(),
+                    },
                 ),
                 OllamaError::ModelNotFound(m) => (
                     StatusCode::UNPROCESSABLE_ENTITY,
-                    format!("model '{m}' is not available — run `ollama pull {m}` first"),
+                    ErrorResponse {
+                        error: format!("model '{m}' is not available"),
+                        code: "OLLAMA_MODEL_NOT_FOUND".to_string(),
+                    },
                 ),
                 OllamaError::MissingKeepAlive => (
                     StatusCode::BAD_REQUEST,
-                    "keep alive is required and cannot be empty".to_string(),
+                    ErrorResponse {
+                        error: "keep_alive is required".to_string(),
+                        code: "OLLAMA_MISSING_KEEPALIVE".to_string(),
+                    },
+                ),
+                OllamaError::InvalidKeepAlive(v) => (
+                    StatusCode::BAD_REQUEST,
+                    ErrorResponse {
+                        error: format!("invalid keep_alive '{v}'"),
+                        code: "OLLAMA_INVALID_KEEPALIVE".to_string(),
+                    },
                 ),
-                OllamaError::InvalidKeepAlive(v) => {
-                    (StatusCode::BAD_REQUEST, format!("invalid keep_alive '{v}'"))
-                }
                 OllamaError::MissingMessages => (
                     StatusCode::BAD_REQUEST,
-                    "messages array with at least one user message is required".to_string(),
+                    ErrorResponse {
+                        error: "messages array required".to_string(),
+                        code: "OLLAMA_MISSING_MESSAGES".to_string(),
+                    },
+                ),
+                OllamaError::Http(e) => (
+                    StatusCode::INTERNAL_SERVER_ERROR,
+                    ErrorResponse {
+                        error: e.to_string(),
+                        code: "OLLAMA_HTTP_ERROR".to_string(),
+                    },
                 ),
-                OllamaError::Http(e) => (StatusCode::INTERNAL_SERVER_ERROR, e.to_string()),
             },
         };
 
-        (status, msg).into_response()
+        (status, Json(body)).into_response()
     }
 }