Merge Codex custom tool support

gitcommit90 · gitcommit90 · commit 571b757b7414 · 2026-07-18T01:27:21.000Z
diff --git a/package-lock.json b/package-lock.json
diff --git a/package.json b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "rerouted",
-  "version": "0.4.15",
+  "version": "0.4.16",
   "description": "A macOS menu-bar router for accounts, models, and automatic fallback.",
   "author": "gitcommit90",
   "license": "MIT",
diff --git a/src/lib/providers/chatgpt.js b/src/lib/providers/chatgpt.js
@@ -139,9 +139,11 @@ function toResponsesInput(messages, model, reasoningScope) {
     }
     if (message.role === "tool") {
       input.push({
-        type: "function_call_output",
+        type: message.extra_content?.openai?.custom_tool_call_output ? "custom_tool_call_output" : "function_call_output",
         call_id: message.tool_call_id,
-        output: textFromOpenAiContent(message.content),
+        output: message.extra_content?.openai?.custom_tool_call_output && Array.isArray(message.content)
+          ? JSON.parse(JSON.stringify(message.content))
+          : textFromOpenAiContent(message.content),
       });
       continue;
     }
@@ -167,7 +169,8 @@ function toResponsesInput(messages, model, reasoningScope) {
     }
     const emittedReasoning = new Set();
     for (const call of calls) {
-      if (!call?.function?.name) continue;
+      const custom = call?.type === "custom" && call.custom?.name;
+      if (!custom && !call?.function?.name) continue;
       const echoedReasoning = reasoningItemsFromToolCall(call);
       const reasoningItems = echoedReasoning.length
         ? echoedReasoning
@@ -178,7 +181,12 @@ function toResponsesInput(messages, model, reasoningScope) {
         emittedReasoning.add(identity);
         input.push(reasoning);
       }
-      input.push({
+      input.push(custom ? {
+        type: "custom_tool_call",
+        call_id: call.id,
+        name: call.custom.name,
+        input: typeof call.custom.input === "string" ? call.custom.input : String(call.custom.input ?? ""),
+      } : {
         type: "function_call",
         call_id: call.id,
         name: call.function.name,
@@ -264,11 +272,14 @@ function fromResponsesJson(data, model, { reasoningScope } = {}) {
       for (const c of item.content) {
         if (c.type === "output_text" || c.type === "text") text += c.text || "";
       }
-    } else if (item.type === "function_call" && item.name) {
+    } else if ((item.type === "function_call" || item.type === "custom_tool_call") && item.name) {
+      const custom = item.type === "custom_tool_call";
       const call = {
         id: item.call_id || item.id,
-        type: "function",
-        function: { name: item.name, arguments: item.arguments || "" },
+        type: custom ? "custom" : "function",
+        ...(custom
+          ? { custom: { name: item.name, input: item.input || "" } }
+          : { function: { name: item.name, arguments: item.arguments || "" } }),
       };
       attachReasoningItems(call, reasoningByCall.get(call.id) || []);
       toolCalls.push(call);
@@ -434,33 +445,55 @@ async function pipeResponsesSse(
       }
       if (
         (type === "response.output_item.added" || type === "response.output_item.done") &&
-        item?.type === "function_call" &&
+        (item?.type === "function_call" || item?.type === "custom_tool_call") &&
         item.name
       ) {
         const index = toolIndexFor(data, item);
         const current = toolCalls[index];
+        const custom = item.type === "custom_tool_call";
         current.id ||= item.call_id || item.id;
-        current.function.name ||= item.name;
-        if (!current.function.arguments && item.arguments) {
-          current.function.arguments = item.arguments;
+        if (custom) {
+          current.type = "custom";
+          current.custom = { name: item.name, input: item.input || current.custom?.input || "" };
+          delete current.function;
+        } else {
+          current.function.name ||= item.name;
+          if (!current.function.arguments && item.arguments) current.function.arguments = item.arguments;
         }
         if (type === "response.output_item.added") {
           ensureRole();
-          writeChunk(
-            openaiChunk({
-              id,
-              model,
-              tool_calls: [
-                {
-                  index,
-                  id: current.id,
-                  type: "function",
-                  function: { name: current.function.name, arguments: "" },
-                },
-              ],
-            })
-          );
+          writeChunk(openaiChunk({
+            id,
+            model,
+            tool_calls: [{
+              index,
+              id: current.id,
+              type: custom ? "custom" : "function",
+              ...(custom
+                ? { custom: { name: current.custom.name, input: "" } }
+                : { function: { name: current.function.name, arguments: "" } }),
+            }],
+          }));
         }
+      } else if (type === "response.custom_tool_call_input.delta") {
+        const index = toolIndexFor(data, item);
+        const delta = typeof data.delta === "string" ? data.delta : "";
+        const current = toolCalls[index];
+        current.type = "custom";
+        current.custom ||= { name: "", input: "" };
+        current.custom.input += delta;
+        delete current.function;
+        if (delta) {
+          ensureRole();
+          writeChunk(openaiChunk({ id, model, tool_calls: [{ index, type: "custom", custom: { input: delta } }] }));
+        }
+      } else if (type === "response.custom_tool_call_input.done") {
+        const index = toolIndexFor(data, item);
+        const current = toolCalls[index];
+        current.type = "custom";
+        current.custom ||= { name: "", input: "" };
+        if (!current.custom.input && typeof data.input === "string") current.custom.input = data.input;
+        delete current.function;
       } else if (type === "response.function_call_arguments.delta") {
         const index = toolIndexFor(data, item);
         const delta = typeof data.delta === "string" ? data.delta : "";
diff --git a/src/lib/responses-api.js b/src/lib/responses-api.js
@@ -117,6 +117,22 @@ function validateInputItem(item, param) {
     if (!(typeof item.output === "string" || Array.isArray(item.output))) throw invalid("function_call_output requires string or array output", `${param}.output`);
     return;
   }
+  if (item.type === "custom_tool_call") {
+    if (typeof item.call_id !== "string" || !item.call_id) throw invalid("custom_tool_call requires call_id", `${param}.call_id`);
+    if (typeof item.name !== "string" || !item.name) throw invalid("custom_tool_call requires name", `${param}.name`);
+    if (typeof item.input !== "string") throw invalid("custom_tool_call input must be a string", `${param}.input`);
+    return;
+  }
+  if (item.type === "custom_tool_call_output") {
+    if (typeof item.call_id !== "string" || !item.call_id) throw invalid("custom_tool_call_output requires call_id", `${param}.call_id`);
+    if (!(typeof item.output === "string" || Array.isArray(item.output))) {
+      throw invalid("custom_tool_call_output requires string or array output", `${param}.output`);
+    }
+    if (Array.isArray(item.output)) {
+      item.output.forEach((part, index) => validateContentPart(part, `${param}.output[${index}]`));
+    }
+    return;
+  }
   if (item.type !== undefined && item.type !== "message") throw invalid("Unsupported input item", `${param}.type`);
   if (!["user", "assistant", "system", "developer"].includes(item.role)) throw invalid("Invalid message role", `${param}.role`);
   if (item.content == null) {
@@ -142,15 +158,18 @@ function inputMessages(input) {
       if (reasoning) pendingReasoning.push(reasoning);
       continue;
     }
-    if (item.type === "function_call") {
+    if (item.type === "function_call" || item.type === "custom_tool_call") {
       if (!pendingAssistant) {
         pendingAssistant = { role: "assistant", content: null, tool_calls: [] };
         messages.push(pendingAssistant);
       }
+      const custom = item.type === "custom_tool_call";
       const call = {
         id: item.call_id,
-        type: "function",
-        function: { name: item.name, arguments: item.arguments },
+        type: custom ? "custom" : "function",
+        ...(custom
+          ? { custom: { name: item.name, input: item.input } }
+          : { function: { name: item.name, arguments: item.arguments } }),
       };
       if (pendingReasoning.length) {
         call.extra_content = { openai: { reasoning_items: pendingReasoning.map((reasoning) => ({ ...reasoning })) } };
@@ -160,8 +179,15 @@ function inputMessages(input) {
     }
     pendingAssistant = null;
     pendingReasoning = [];
-    if (item.type === "function_call_output") {
-      messages.push({ role: "tool", tool_call_id: item.call_id, content: textContent(item.output) });
+    if (item.type === "function_call_output" || item.type === "custom_tool_call_output") {
+      messages.push({
+        role: "tool",
+        tool_call_id: item.call_id,
+        content: item.type === "custom_tool_call_output" && Array.isArray(item.output)
+          ? JSON.parse(JSON.stringify(item.output))
+          : textContent(item.output),
+        ...(item.type === "custom_tool_call_output" ? { extra_content: { openai: { custom_tool_call_output: true } } } : {}),
+      });
       continue;
     }
     messages.push({
@@ -275,7 +301,10 @@ function outputFromMessage(message, responseId, request) {
       }
     }
     const callId = call.id || `call_${crypto.randomUUID().replaceAll("-", "")}`;
-    output.push({ id: `fc_${responseId.slice(5)}_${index}`, type: "function_call", status: "completed", call_id: callId, name: call.function?.name, arguments: call.function?.arguments || "" });
+    const custom = call.type === "custom" && call.custom;
+    output.push(custom
+      ? { id: `ctc_${responseId.slice(5)}_${index}`, type: "custom_tool_call", status: "completed", call_id: callId, name: call.custom.name, input: call.custom.input || "" }
+      : { id: `fc_${responseId.slice(5)}_${index}`, type: "function_call", status: "completed", call_id: callId, name: call.function?.name, arguments: call.function?.arguments || "" });
   }
   return output;
 }
@@ -351,17 +380,26 @@ async function pipeChatCompletionsSseToResponses(streamPipe, sink, model, reques
         if (!call) {
           const outputIndex = slot();
           const callId = callDelta.id || `call_${crypto.randomUUID().replaceAll("-", "")}`;
-          call = { id: `fc_${responseId.slice(5)}_${calls.size}`, call_id: callId, type: "function_call", status: "in_progress", name: callDelta.function?.name || "", arguments: "", argumentDeltas: [], outputIndex, emitted: false };
+          const custom = callDelta.type === "custom" || !!callDelta.custom;
+          call = { id: `${custom ? "ctc" : "fc"}_${responseId.slice(5)}_${calls.size}`, call_id: callId, type: custom ? "custom_tool_call" : "function_call", status: "in_progress", name: custom ? callDelta.custom?.name || "" : callDelta.function?.name || "", input: "", arguments: "", argumentDeltas: [], outputIndex, emitted: false };
           calls.set(key, call);
           entries.push(call);
           if (!deferForReasoning) {
-            const pending = { id: call.id, type: "function_call", status: "in_progress", call_id: call.call_id, name: call.name, arguments: "" };
+            const pending = call.type === "custom_tool_call"
+              ? { id: call.id, type: call.type, status: "in_progress", call_id: call.call_id, name: call.name, input: "" }
+              : { id: call.id, type: call.type, status: "in_progress", call_id: call.call_id, name: call.name, arguments: "" };
             writeEvent(sink, "response.output_item.added", { output_index: outputIndex, item: pending }, sequence++);
             call.emitted = true;
           }
         }
         if (callDelta.id) call.call_id = callDelta.id;
         if (callDelta.function?.name) call.name = callDelta.function.name;
+        if (callDelta.custom?.name) call.name = callDelta.custom.name;
+        if (callDelta.custom?.input) {
+          call.input += callDelta.custom.input;
+          call.argumentDeltas.push(callDelta.custom.input);
+          if (call.emitted) writeEvent(sink, "response.custom_tool_call_input.delta", { item_id: call.id, output_index: call.outputIndex, delta: callDelta.custom.input }, sequence++);
+        }
         if (callDelta.function?.arguments) {
           call.arguments += callDelta.function.arguments;
           call.argumentDeltas.push(callDelta.function.arguments);
@@ -406,13 +444,21 @@ async function pipeChatCompletionsSseToResponses(streamPipe, sink, model, reques
         writeEvent(sink, "response.output_item.done", { output_index: outputIndex, item }, sequence++);
       } else {
         if (!entry.emitted) {
-          const pending = { id: entry.id, type: "function_call", status: "in_progress", call_id: entry.call_id, name: entry.name, arguments: "" };
+          const custom = entry.type === "custom_tool_call";
+          const pending = custom
+            ? { id: entry.id, type: entry.type, status: "in_progress", call_id: entry.call_id, name: entry.name, input: "" }
+            : { id: entry.id, type: entry.type, status: "in_progress", call_id: entry.call_id, name: entry.name, arguments: "" };
           writeEvent(sink, "response.output_item.added", { output_index: outputIndex, item: pending }, sequence++);
-          for (const delta of entry.argumentDeltas) writeEvent(sink, "response.function_call_arguments.delta", { item_id: entry.id, output_index: outputIndex, delta }, sequence++);
+          for (const delta of entry.argumentDeltas) writeEvent(sink, custom ? "response.custom_tool_call_input.delta" : "response.function_call_arguments.delta", { item_id: entry.id, output_index: outputIndex, delta }, sequence++);
         }
-        const item = { id: entry.id, type: "function_call", status: "completed", call_id: entry.call_id, name: entry.name, arguments: entry.arguments };
+        const custom = entry.type === "custom_tool_call";
+        const item = custom
+          ? { id: entry.id, type: entry.type, status: "completed", call_id: entry.call_id, name: entry.name, input: entry.input }
+          : { id: entry.id, type: entry.type, status: "completed", call_id: entry.call_id, name: entry.name, arguments: entry.arguments };
         output.push(item);
-        writeEvent(sink, "response.function_call_arguments.done", { item_id: item.id, output_index: outputIndex, arguments: item.arguments }, sequence++);
+        writeEvent(sink, custom ? "response.custom_tool_call_input.done" : "response.function_call_arguments.done", custom
+          ? { item_id: item.id, output_index: outputIndex, input: item.input }
+          : { item_id: item.id, output_index: outputIndex, arguments: item.arguments }, sequence++);
         writeEvent(sink, "response.output_item.done", { output_index: outputIndex, item }, sequence++);
       }
     }
diff --git a/tests/chatgpt-tools.test.js b/tests/chatgpt-tools.test.js
@@ -70,6 +70,40 @@ describe("ChatGPT Responses tool translation", () => {
     assert.equal(typeof result.reasoningScope, "string");
   });
 
+  it("preserves captured additional_tools custom grammar and replays custom output", () => {
+    const additionalTools = [
+      { type: "custom", name: "exec", description: "Runs a shell command and returns its output.", format: { type: "grammar", syntax: "lark", definition: "start: command\ncommand: /(.|\\n)+/" } },
+      { type: "namespace", name: "container", description: "Container tools", tools: [{ type: "custom", name: "exec", format: { type: "grammar", syntax: "regex", definition: "(?s).+" } }] },
+    ];
+    const first = chatgpt.toResponsesBody({ messages: [{ role: "user", content: "List files" }], tools: additionalTools }, "gpt-5.6-sol", false);
+    assert.deepEqual(first.tools, additionalTools);
+    const output = [
+      { type: "input_text", text: "Script completed..." },
+      { type: "input_text", text: "{...TOOL_EXEC_OK...}" },
+    ];
+    const second = chatgpt.toResponsesBody({ messages: [
+      { role: "assistant", content: null, tool_calls: [{ id: "call_capture", type: "custom", custom: { name: "exec", input: "ls" } }] },
+      { role: "tool", tool_call_id: "call_capture", content: output, extra_content: { openai: { custom_tool_call_output: true } } },
+    ], tools: additionalTools }, "gpt-5.6-sol", false);
+    assert.deepEqual(second.input, [
+      { type: "custom_tool_call", call_id: "call_capture", name: "exec", input: "ls" },
+      { type: "custom_tool_call_output", call_id: "call_capture", output },
+    ]);
+    assert.deepEqual(second.tools, additionalTools);
+  });
+
+  it("collects custom tool events without converting them to function calls", async () => {
+    const events = [
+      { type: "response.output_item.added", output_index: 1, item: { id: "ctc_1", type: "custom_tool_call", call_id: "call_exec", name: "exec", input: "" } },
+      { type: "response.custom_tool_call_input.delta", item_id: "ctc_1", output_index: 1, delta: "pw" },
+      { type: "response.custom_tool_call_input.done", item_id: "ctc_1", output_index: 1, input: "pwd" },
+      { type: "response.output_item.done", output_index: 1, item: { id: "ctc_1", type: "custom_tool_call", call_id: "call_exec", name: "exec", input: "pwd" } },
+      { type: "response.completed" },
+    ].map((event) => `data: ${JSON.stringify(event)}\n\n`);
+    const result = await chatgpt.pipeResponsesSse(Readable.from(events), null, "gpt-5.6-sol", { collect: true });
+    assert.deepEqual(result.choices[0].message.tool_calls, [{ id: "call_exec", type: "custom", custom: { name: "exec", input: "pwd" } }]);
+  });
+
   it("preserves assistant tool calls and tool results in multi-turn input", () => {
     const payload = chatgpt.toResponsesBody(
       {
diff --git a/tests/responses-api.test.js b/tests/responses-api.test.js

Original file line number	Diff line number	Diff line change
`@@ -1,6 +1,6 @@`
`1`	`1`	`{`
`2`	`2`	`"name": "rerouted",`
`3`		`- "version": "0.4.15",`
	`3`	`+ "version": "0.4.16",`
`4`	`4`	`"description": "A macOS menu-bar router for accounts, models, and automatic fallback.",`
`5`	`5`	`"author": "gitcommit90",`
`6`	`6`	`"license": "MIT",`