openAI API support implemented

Author: AdamBien

README.md

@@ -75,7 +75,59 @@ anthropic.api.key=sk-ant-...
 anthropic.version=2023-06-01
 ```
 
-The default model is `claude-opus-4-6`. Override via system property:
+### LLM Provider
+
+zsmith ships with two clients, selected at runtime via `llm.provider`:
+
+```properties
+llm.provider=claude     # default — Anthropic Messages API
+# llm.provider=openai   # OpenAI Chat Completions API
+```
+
+Agent code is unchanged either way — request and response are translated internally so the Agent loop only ever sees Anthropic-shaped content blocks.
+
+#### Claude endpoint
+
+By default, requests go to `https://api.anthropic.com/v1/messages`. To point at a local Anthropic-compatible endpoint:
+
+```properties
+claude.scheme=http
+claude.host=localhost
+claude.port=8080
+```
+
+`claude.port` is optional — omit it to use the scheme default. `claude.scheme` defaults to `https`, `claude.host` to `api.anthropic.com`. The path `/v1/messages` is fixed.
+
+#### OpenAI endpoint
+
+By default, requests go to `https://api.openai.com/v1/chat/completions`. Configurable knobs:
+
+```properties
+openai.api.key=sk-...      # optional — omitted Authorization header when blank (useful for local servers)
+openai.model=gpt-4o        # default
+openai.max.tokens=4096     # default
+openai.scheme=https        # default
+openai.host=api.openai.com # default
+openai.port=                # default unset (uses scheme default port)
+```
+
+The OpenAI client has no fallback model — unlike Claude's 529→fallback retry, OpenAI errors propagate directly.
+
+To point at a local Ollama server:
+
+```properties
+llm.provider=openai
+openai.host=localhost
+openai.port=11434
+openai.scheme=http
+openai.model=llama3.1
+```
+
+LM Studio (default port 1234), llama.cpp `--api`, and vLLM expose the same Chat Completions shape and work identically.
+
+### Model
+
+The default Claude model is `claude-opus-4-6`. Override via system property:
 
 ```bash
 java -Dmodel=sonnet -cp zbo/zsmith.jar MyAgent.java

version.txt

@@ -0,0 +1 @@
+2026.05.20.01

zsmith/src/main/java/airhacks/zsmith/agent/boundary/Agent.java

@@ -15,7 +15,7 @@
 
 import airhacks.zsmith.agent.control.Version;
 import airhacks.zsmith.agent.entity.AgentTurnEvent;
-import airhacks.zsmith.claude.control.Claude;
+import airhacks.zsmith.llm.control.LLM;
 import airhacks.zsmith.configuration.control.ZCfg;
 import airhacks.zsmith.episodicmemory.boundary.EpisodicMemoryStore;
 import airhacks.zsmith.episodicmemory.control.RecallMemoryTool;
@@ -273,12 +273,12 @@ public String chat(String userMessage) {
             turnEvent.begin();
             try {
                 progress.update(iteration + 1);
-                var response = Claude.invoke(
+                var response = LLM.invoke(
                         this.systemPrompt,
                         this.memory.toJSON(),
                         toolDefinitions(),
                         this.temperature);
-                progress.addClaudeInvocation();
+                progress.addLLMInvocation();
 
                 var content = response.getJSONArray("content");
                 var stopReason = response.optString("stop_reason", "end_turn");

zsmith/src/main/java/airhacks/zsmith/claude/control/Claude.java

@@ -21,11 +21,17 @@
 
 public interface Claude {
 
-    String ANTHROPIC_VERSION = ZCfg.requiredString("anthropic.version");
-    String ANTHROPIC_API_KEY = ZCfg.requiredString("anthropic.api.key");
     Models defaultModel = Models.CLAUDE_47_OPUS;
     String fallbackModelName = "claude-sonnet-4-6";
 
+    static String apiKey() {
+        return ZCfg.requiredString("anthropic.api.key");
+    }
+
+    static String apiVersion() {
+        return ZCfg.requiredString("anthropic.version");
+    }
+
     enum Models {
         CLAUDE_47_OPUS("claude-opus-4-7", Claude.fallbackModelName, false, true, true, 32_000),
         CLAUDE_46_OPUS("claude-opus-4-6", Claude.fallbackModelName, true, true, true, 32_000),
@@ -96,9 +102,17 @@ public static Optional<Models> fromPartialMatch(String partialName) {
     }
 
     HttpClient client = HttpClient.newHttpClient();
-    URI uri = URI.create("https://api.anthropic.com/v1/messages");
+    URI uri = endpoint();
     Models currentModel = Models.fromSystemProperty();
 
+    static URI endpoint() {
+        var scheme = ZCfg.string("claude.scheme", "https");
+        var host = ZCfg.string("claude.host", "api.anthropic.com");
+        var port = ZCfg.integer("claude.port", -1);
+        var authority = port > 0 ? host + ":" + port : host;
+        return URI.create("%s://%s/v1/messages".formatted(scheme, authority));
+    }
+
     static JSONObject invoke(String system, JSONArray messages, JSONArray tools, float temperature) {
         var payloadJSON = claudeMessage(messages, temperature, system);
         payloadJSON.put("model", currentModel.modelName());
@@ -249,9 +263,9 @@ static String replaceModel(String message, String originalModel, String fallback
     static HttpResponse<String> send(String message) {
         var request = HttpRequest.newBuilder(uri)
                 .POST(BodyPublishers.ofString(message))
-                .header("x-api-key", ANTHROPIC_API_KEY)
+                .header("x-api-key", apiKey())
                 .header("content-type", "application/json")
-                .header("anthropic-version", ANTHROPIC_VERSION)
+                .header("anthropic-version", apiVersion())
                 .build();
         try {
             return client.send(request, BodyHandlers.ofString());

zsmith/src/main/java/airhacks/zsmith/llm/control/LLM.java

@@ -0,0 +1,24 @@
+package airhacks.zsmith.llm.control;
+
+import org.json.JSONArray;
+import org.json.JSONObject;
+
+import airhacks.zsmith.claude.control.Claude;
+import airhacks.zsmith.configuration.control.ZCfg;
+import airhacks.zsmith.openai.control.OpenAI;
+
+public interface LLM {
+
+    static String provider() {
+        return ZCfg.string("llm.provider", "claude");
+    }
+
+    static JSONObject invoke(String system, JSONArray messages, JSONArray tools, float temperature) {
+        return switch (provider()) {
+            case "openai" -> OpenAI.invoke(system, messages, tools, temperature);
+            case "claude" -> Claude.invoke(system, messages, tools, temperature);
+            default -> throw new IllegalStateException(
+                "unknown llm.provider '%s' — expected 'claude' or 'openai'".formatted(provider()));
+        };
+    }
+}

zsmith/src/main/java/airhacks/zsmith/logging/control/ProgressBar.java

@@ -8,15 +8,15 @@ public class ProgressBar {
     static final String RESET = "\u001B[0m";
 
     private final int maxIterations;
-    private int claudeInvocations;
+    private int llmInvocations;
     private int toolInvocations;
 
     public ProgressBar(int maxIterations) {
         this.maxIterations = maxIterations;
     }
 
-    public void addClaudeInvocation() {
-        this.claudeInvocations++;
+    public void addLLMInvocation() {
+        this.llmInvocations++;
     }
 
     public void addToolInvocations(int count) {
@@ -40,7 +40,7 @@ String render(int iteration) {
                 + violet + EMPTY.repeat(empty) + RESET
                 + blue + "]" + RESET
                 + "  " + iteration + "/" + maxIterations
-                + "  " + cyan + "claude: " + claudeInvocations + RESET
+                + "  " + cyan + "llm: " + llmInvocations + RESET
                 + "  " + magenta + "tools: " + toolInvocations + RESET;
     }
 
@@ -49,7 +49,7 @@ public void summary() {
         var magenta = Log.Color.MAGENTA.code;
         var green = Log.Color.GREEN.code;
         System.out.println(green + "--- summary ---" + RESET
-                + "  " + cyan + "claude: " + claudeInvocations + RESET
+                + "  " + cyan + "llm: " + llmInvocations + RESET
                 + "  " + magenta + "tools: " + toolInvocations + RESET);
     }
 }