feat: support models by OpenAI API using "name from url" syntax

pkg/remote/remote.go

@@ -3,6 +3,8 @@ package remote
 import (
 	"context"
 	"fmt"
+	"net/url"
+	"os"
 	"slices"
 	"sort"
 	"strings"
@@ -87,6 +89,28 @@ func (c *Client) Supports(ctx context.Context, modelName string) (bool, error) {
 	return true, nil
 }
 
+func isHTTPURL(toolName string) bool {
+	return strings.HasPrefix(toolName, "http://") ||
+		strings.HasPrefix(toolName, "https://")
+}
+
+func (c *Client) clientFromURL(apiURL string) (*openai.Client, error) {
+	parsed, err := url.Parse(apiURL)
+	if err != nil {
+		return nil, err
+	}
+	env := strings.ToUpper(strings.ReplaceAll(parsed.Hostname(), ".", "_")) + "_API_KEY"
+	apiKey := os.Getenv(env)
+	if apiKey == "" {
+		apiKey = "<unset>"
+	}
+	return openai.NewClient(openai.Options{
+		BaseURL: apiURL,
+		Cache:   c.cache,
+		APIKey:  apiKey,
+	})
+}
+
 func (c *Client) load(ctx context.Context, toolName string) (*openai.Client, error) {
 	c.clientsLock.Lock()
 	defer c.clientsLock.Unlock()
@@ -96,6 +120,19 @@ func (c *Client) load(ctx context.Context, toolName string) (*openai.Client, err
 		return client, nil
 	}
 
+	if c.clients == nil {
+		c.clients = make(map[string]*openai.Client)
+	}
+
+	if isHTTPURL(toolName) {
+		remoteClient, err := c.clientFromURL(toolName)
+		if err != nil {
+			return nil, err
+		}
+		c.clients[toolName] = remoteClient
+		return remoteClient, nil
+	}
+
 	prg, err := loader.Program(ctx, toolName, "")
 	if err != nil {
 		return nil, err
@@ -120,10 +157,6 @@ func (c *Client) load(ctx context.Context, toolName string) (*openai.Client, err
 		return nil, err
 	}
 
-	if c.clients == nil {
-		c.clients = make(map[string]*openai.Client)
-	}
-
 	c.clients[toolName] = client
 	return client, nil
 }