[Docs] Agent Gateway (#17454)

* init litellm A2a client

* simpler a2a client interface

* test a2a

* move a2a invoking tests

* test fix

* ensure a2a send message is tracked n logs

* rename tags

* add streaming handlng

* add a2a invocation

* add a2a invocation i cost calc

* test_a2a_logging_payload

* update invoke_agent_a2a

* test_invoke_agent_a2a_adds_litellm_data

* add A2a agent

* fix endpoints on A2a

* UI allow testing a2a endpoints

* add agent imgs

* add a2a as an endpoint

* add a2a

* docs a2a invoke

* docs a2a

* docs A2a invoke

docs/my-website/docs/a2a.md

@@ -0,0 +1,198 @@
+import Tabs from '@theme/Tabs';
+import TabItem from '@theme/TabItem';
+import Image from '@theme/IdealImage';
+
+# /a2a - Agent Gateway (A2A Protocol)
+
+| Feature | Supported | 
+|---------|-----------|
+| Logging | ✅ |
+| Load Balancing | ✅ |
+| Streaming | ✅ |
+
+:::tip
+
+LiteLLM follows the [A2A (Agent-to-Agent) Protocol](https://github.com/google/A2A) for invoking agents.
+
+:::
+
+## Adding your Agent
+
+You can add A2A-compatible agents through the LiteLLM Admin UI.
+
+1. Navigate to the **Agents** tab
+2. Click **Add Agent**
+3. Enter the agent name (e.g., `ij-local`) and the URL of your A2A agent
+
+<Image 
+  img={require('../img/add_agent_1.png')}
+  style={{width: '80%', display: 'block', margin: '0'}}
+/>
+
+The URL should be the invocation URL for your A2A agent (e.g., `http://localhost:10001`).
+
+## Invoking your Agents
+
+Use the [A2A Python SDK](https://pypi.org/project/a2a/) to invoke agents through LiteLLM:
+
+- `base_url`: Your LiteLLM proxy URL + `/a2a/{agent_name}`
+- `headers`: Include your LiteLLM Virtual Key for authentication
+
+```python showLineNumbers title="invoke_a2a_agent.py"
+from uuid import uuid4
+import httpx
+import asyncio
+from a2a.client import A2ACardResolver, A2AClient
+from a2a.types import MessageSendParams, SendMessageRequest
+
+# === CONFIGURE THESE ===
+LITELLM_BASE_URL = "http://localhost:4000"  # Your LiteLLM proxy URL
+LITELLM_VIRTUAL_KEY = "sk-1234"             # Your LiteLLM Virtual Key
+LITELLM_AGENT_NAME = "ij-local"             # Agent name registered in LiteLLM
+# =======================
+
+async def main():
+    base_url = f"{LITELLM_BASE_URL}/a2a/{LITELLM_AGENT_NAME}"
+    headers = {"Authorization": f"Bearer {LITELLM_VIRTUAL_KEY}"}
+    
+    async with httpx.AsyncClient(headers=headers) as httpx_client:
+        # Resolve agent card and create client
+        resolver = A2ACardResolver(httpx_client=httpx_client, base_url=base_url)
+        agent_card = await resolver.get_agent_card()
+        client = A2AClient(httpx_client=httpx_client, agent_card=agent_card)
+
+        # Send a message
+        request = SendMessageRequest(
+            id=str(uuid4()),
+            params=MessageSendParams(
+                message={
+                    "role": "user",
+                    "parts": [{"kind": "text", "text": "Hello, what can you do?"}],
+                    "messageId": uuid4().hex,
+                }
+            ),
+        )
+        response = await client.send_message(request)
+        print(response.model_dump(mode="json", exclude_none=True))
+
+if __name__ == "__main__":
+    asyncio.run(main())
+```
+
+### Streaming Responses
+
+For streaming responses, use `send_message_streaming`:
+
+```python showLineNumbers title="invoke_a2a_agent_streaming.py"
+from uuid import uuid4
+import httpx
+import asyncio
+from a2a.client import A2ACardResolver, A2AClient
+from a2a.types import MessageSendParams, SendStreamingMessageRequest
+
+# === CONFIGURE THESE ===
+LITELLM_BASE_URL = "http://localhost:4000"  # Your LiteLLM proxy URL
+LITELLM_VIRTUAL_KEY = "sk-1234"             # Your LiteLLM Virtual Key
+LITELLM_AGENT_NAME = "ij-local"             # Agent name registered in LiteLLM
+# =======================
+
+async def main():
+    base_url = f"{LITELLM_BASE_URL}/a2a/{LITELLM_AGENT_NAME}"
+    headers = {"Authorization": f"Bearer {LITELLM_VIRTUAL_KEY}"}
+    
+    async with httpx.AsyncClient(headers=headers) as httpx_client:
+        # Resolve agent card and create client
+        resolver = A2ACardResolver(httpx_client=httpx_client, base_url=base_url)
+        agent_card = await resolver.get_agent_card()
+        client = A2AClient(httpx_client=httpx_client, agent_card=agent_card)
+
+        # Send a streaming message
+        request = SendStreamingMessageRequest(
+            id=str(uuid4()),
+            params=MessageSendParams(
+                message={
+                    "role": "user",
+                    "parts": [{"kind": "text", "text": "Hello, what can you do?"}],
+                    "messageId": uuid4().hex,
+                }
+            ),
+        )
+        
+        # Stream the response
+        async for chunk in client.send_message_streaming(request):
+            print(chunk.model_dump(mode="json", exclude_none=True))
+
+if __name__ == "__main__":
+    asyncio.run(main())
+```
+
+## Tracking Agent Logs
+
+After invoking an agent, you can view the request logs in the LiteLLM **Logs** tab.
+
+The logs show:
+- **Request/Response content** sent to and received from the agent
+- **User, Key, Team** information for tracking who made the request
+- **Latency and cost** metrics
+
+<Image 
+  img={require('../img/agent2.png')}
+  style={{width: '100%', display: 'block', margin: '2rem auto'}}
+/>
+
+## API Reference
+
+### Endpoint
+
+```
+POST /a2a/{agent_name}/message/send
+```
+
+### Authentication
+
+Include your LiteLLM Virtual Key in the `Authorization` header:
+
+```
+Authorization: Bearer sk-your-litellm-key
+```
+
+### Request Format
+
+LiteLLM follows the [A2A JSON-RPC 2.0 specification](https://github.com/google/A2A):
+
+```json title="Request Body"
+{
+  "jsonrpc": "2.0",
+  "id": "unique-request-id",
+  "method": "message/send",
+  "params": {
+    "message": {
+      "role": "user",
+      "parts": [{"kind": "text", "text": "Your message here"}],
+      "messageId": "unique-message-id"
+    }
+  }
+}
+```
+
+### Response Format
+
+```json title="Response"
+{
+  "jsonrpc": "2.0",
+  "id": "unique-request-id",
+  "result": {
+    "kind": "task",
+    "id": "task-id",
+    "contextId": "context-id",
+    "status": {"state": "completed", "timestamp": "2025-01-01T00:00:00Z"},
+    "artifacts": [
+      {
+        "artifactId": "artifact-id",
+        "name": "response",
+        "parts": [{"kind": "text", "text": "Agent response here"}]
+      }
+    ]
+  }
+}
+```

docs/my-website/sidebars.js

@@ -316,6 +316,7 @@ const sidebars = {
         slug: "/supported_endpoints",
       },
       items: [
+        "a2a",
         "assistants",
         {
           type: "category",

litellm/proxy/agent_endpoints/a2a_endpoints.py

@@ -115,6 +115,16 @@ async def get_agent_card(
     tags=["[beta] A2A Agents"],
     dependencies=[Depends(user_api_key_auth)],
 )
+@router.post(
+    "/a2a/{agent_id}/message/send",
+    tags=["[beta] A2A Agents"],
+    dependencies=[Depends(user_api_key_auth)],
+)
+@router.post(
+    "/v1/a2a/{agent_id}/message/send",
+    tags=["[beta] A2A Agents"],
+    dependencies=[Depends(user_api_key_auth)],
+)
 async def invoke_agent_a2a(
     agent_id: str,
     request: Request,

provider_endpoints_support.json

@@ -17,7 +17,8 @@
         "rerank": "Supports /rerank endpoint",
         "ocr": "Supports /ocr endpoint",
         "search": "Supports /search endpoint",
-        "skills": "Supports /skills endpoint"
+        "skills": "Supports /skills endpoint",
+        "a2a_(Agent Gateway)": "Supports /a2a/{agent}/message/send endpoint (A2A Protocol)"
       }
     }
   },
@@ -35,7 +36,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "ai21": {
@@ -51,7 +53,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "ai21_chat": {
@@ -67,7 +70,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "anthropic": {
@@ -84,7 +88,8 @@
         "moderations": false,
         "batches": true,
         "rerank": false,
-        "skills": true
+        "skills": true,
+        "a2a": true
       }
     },
     "anthropic_text": {
@@ -101,7 +106,8 @@
         "moderations": false,
         "batches": true,
         "rerank": false,
-        "skills": true
+        "skills": true,
+        "a2a": true
       }
     },
     "assemblyai": {
@@ -117,7 +123,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "auto_router": {
@@ -133,7 +140,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "bedrock": {
@@ -149,7 +157,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": true
+        "rerank": true,
+        "a2a": true
       }
     },
     "sagemaker": {
@@ -165,7 +174,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "azure": {
@@ -181,7 +191,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "azure_ai": {
@@ -198,7 +209,8 @@
         "moderations": true,
         "batches": true,
         "rerank": false,
-        "ocr": true
+        "ocr": true,
+        "a2a": true
       }
     },
     "azure_ai/doc-intelligence": {
@@ -231,7 +243,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "baseten": {
@@ -247,7 +260,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "bytez": {
@@ -263,7 +277,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "cerebras": {
@@ -279,7 +294,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "clarifai": {
@@ -295,7 +311,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "cloudflare": {
@@ -311,7 +328,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "codestral": {
@@ -327,7 +345,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "cohere": {
@@ -343,7 +362,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": true
+        "rerank": true,
+        "a2a": true
       }
     },
     "cohere_chat": {
@@ -359,7 +379,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "cometapi": {
@@ -375,7 +396,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "compactifai": {
@@ -391,7 +413,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "custom": {
@@ -407,7 +430,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "custom_openai": {
@@ -423,7 +447,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "dashscope": {
@@ -439,7 +464,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "databricks": {
@@ -455,7 +481,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "dataforseo": {
@@ -488,7 +515,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "deepgram": {
@@ -504,7 +532,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "deepinfra": {
@@ -520,7 +549,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "deepseek": {
@@ -536,7 +566,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "elevenlabs": {
@@ -552,7 +583,8 @@
         "audio_speech": true,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "exa_ai": {
@@ -585,7 +617,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "fal_ai": {
@@ -601,7 +634,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "featherless_ai": {
@@ -617,7 +651,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "fireworks_ai": {
@@ -633,7 +668,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "firecrawl": {
@@ -666,7 +702,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "galadriel": {
@@ -682,7 +719,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "github_copilot": {
@@ -698,7 +736,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "github": {
@@ -714,7 +753,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "vertex_ai": {
@@ -731,7 +771,8 @@
         "moderations": false,
         "batches": false,
         "rerank": false,
-        "ocr": true
+        "ocr": true,
+        "a2a": true
       }
     },
     "vertex_ai/chirp": {
@@ -763,7 +804,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "gradient_ai": {
@@ -779,7 +821,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "groq": {
@@ -795,7 +838,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "heroku": {
@@ -811,7 +855,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "hosted_vllm": {
@@ -827,7 +872,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "huggingface": {
@@ -843,7 +889,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": true
+        "rerank": true,
+        "a2a": true
       }
     },
     "hyperbolic": {
@@ -859,7 +906,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "watsonx": {
@@ -875,7 +923,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "infinity": {
@@ -923,7 +972,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "lemonade": {
@@ -939,7 +989,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "litellm_proxy": {
@@ -955,7 +1006,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "llamafile": {
@@ -971,7 +1023,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "lm_studio": {
@@ -987,7 +1040,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "maritalk": {
@@ -1003,7 +1057,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "meta_llama": {
@@ -1019,7 +1074,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "mistral": {
@@ -1036,7 +1092,8 @@
         "moderations": false,
         "batches": false,
         "rerank": false,
-        "ocr": true
+        "ocr": true,
+        "a2a": true
       }
     },
     "moonshot": {
@@ -1052,7 +1109,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "docker_model_runner": {
@@ -1068,7 +1126,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "morph": {
@@ -1084,7 +1143,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "nebius": {
@@ -1100,7 +1160,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "nlp_cloud": {
@@ -1116,7 +1177,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "novita": {
@@ -1132,7 +1194,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "nscale": {
@@ -1148,7 +1211,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "nvidia_nim": {
@@ -1164,7 +1228,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "oci": {
@@ -1180,7 +1245,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "ollama": {
@@ -1196,7 +1262,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "ollama_chat": {
@@ -1212,7 +1279,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "oobabooga": {
@@ -1228,7 +1296,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "openai": {
@@ -1244,7 +1313,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "openai_like": {
@@ -1276,7 +1346,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "ovhcloud": {
@@ -1292,7 +1363,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "parallel_ai": {
@@ -1326,7 +1398,8 @@
         "moderations": false,
         "batches": false,
         "rerank": false,
-        "search": true
+        "search": true,
+        "a2a": true
       }
     },
     "petals": {
@@ -1342,7 +1415,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "publicai": {
@@ -1358,7 +1432,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "predibase": {
@@ -1374,7 +1449,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "recraft": {
@@ -1406,7 +1482,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "runwayml": {
@@ -1439,7 +1516,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "searxng": {
@@ -1472,7 +1550,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "snowflake": {
@@ -1488,7 +1567,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "text-completion-codestral": {
@@ -1504,7 +1584,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "text-completion-openai": {
@@ -1520,7 +1601,8 @@
         "audio_speech": true,
         "moderations": true,
         "batches": true,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "together_ai": {
@@ -1536,7 +1618,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "topaz": {
@@ -1552,7 +1635,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "tavily": {
@@ -1585,7 +1669,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "v0": {
@@ -1601,7 +1686,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "vercel_ai_gateway": {
@@ -1617,7 +1703,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "vllm": {
@@ -1633,7 +1720,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "volcengine": {
@@ -1649,7 +1737,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "voyage": {
@@ -1681,7 +1770,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "watsonx_text": {
@@ -1697,7 +1787,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "xai": {
@@ -1713,7 +1804,8 @@
         "audio_speech": false,
         "moderations": false,
         "batches": false,
-        "rerank": false
+        "rerank": false,
+        "a2a": true
       }
     },
     "xinference": {

ui/litellm-dashboard/src/components/playground/chat_ui/A2AMetrics.tsx

@@ -0,0 +1,231 @@
+import React, { useState } from "react";
+import { Tooltip, Button } from "antd";
+import {
+  CheckCircleOutlined,
+  ClockCircleOutlined,
+  LoadingOutlined,
+  ExclamationCircleOutlined,
+  CopyOutlined,
+  DownOutlined,
+  RightOutlined,
+  LinkOutlined,
+  FileTextOutlined,
+  RobotOutlined,
+} from "@ant-design/icons";
+
+export interface A2ATaskMetadata {
+  taskId?: string;
+  contextId?: string;
+  status?: {
+    state?: string;
+    timestamp?: string;
+    message?: string;
+  };
+  metadata?: Record<string, any>;
+}
+
+interface A2AMetricsProps {
+  a2aMetadata?: A2ATaskMetadata;
+  timeToFirstToken?: number;
+  totalLatency?: number;
+}
+
+const getStatusIcon = (state?: string) => {
+  switch (state) {
+    case "completed":
+      return <CheckCircleOutlined className="text-green-500" />;
+    case "working":
+    case "submitted":
+      return <LoadingOutlined className="text-blue-500" />;
+    case "failed":
+    case "canceled":
+      return <ExclamationCircleOutlined className="text-red-500" />;
+    default:
+      return <ClockCircleOutlined className="text-gray-500" />;
+  }
+};
+
+const getStatusColor = (state?: string) => {
+  switch (state) {
+    case "completed":
+      return "bg-green-100 text-green-700";
+    case "working":
+    case "submitted":
+      return "bg-blue-100 text-blue-700";
+    case "failed":
+    case "canceled":
+      return "bg-red-100 text-red-700";
+    default:
+      return "bg-gray-100 text-gray-700";
+  }
+};
+
+const formatTimestamp = (timestamp?: string) => {
+  if (!timestamp) return null;
+  try {
+    const date = new Date(timestamp);
+    return date.toLocaleTimeString([], { hour: "2-digit", minute: "2-digit" });
+  } catch {
+    return timestamp;
+  }
+};
+
+const truncateId = (id?: string, length = 8) => {
+  if (!id) return null;
+  return id.length > length ? `${id.substring(0, length)}…` : id;
+};
+
+const copyToClipboard = (text: string) => {
+  navigator.clipboard.writeText(text);
+};
+
+const A2AMetrics: React.FC<A2AMetricsProps> = ({ a2aMetadata, timeToFirstToken, totalLatency }) => {
+  const [showDetails, setShowDetails] = useState(false);
+
+  if (!a2aMetadata && !timeToFirstToken && !totalLatency) return null;
+
+  const { taskId, contextId, status, metadata } = a2aMetadata || {};
+  const formattedTime = formatTimestamp(status?.timestamp);
+
+  return (
+    <div className="a2a-metrics mt-3 pt-2 border-t border-gray-200 text-xs">
+      {/* A2A Metadata Header */}
+      <div className="flex items-center mb-2 text-gray-600">
+        <RobotOutlined className="mr-1.5 text-blue-500" />
+        <span className="font-medium text-gray-700">A2A Metadata</span>
+      </div>
+
+      {/* Main metrics row */}
+      <div className="flex flex-wrap items-center gap-2 text-gray-500 ml-4">
+        {/* Status badge */}
+        {status?.state && (
+          <span className={`inline-flex items-center px-2 py-0.5 rounded-full text-xs font-medium ${getStatusColor(status.state)}`}>
+            {getStatusIcon(status.state)}
+            <span className="ml-1 capitalize">{status.state}</span>
+          </span>
+        )}
+
+        {/* Timestamp */}
+        {formattedTime && (
+          <Tooltip title={status?.timestamp}>
+            <span className="flex items-center">
+              <ClockCircleOutlined className="mr-1" />
+              {formattedTime}
+            </span>
+          </Tooltip>
+        )}
+
+        {/* Latency */}
+        {totalLatency !== undefined && (
+          <Tooltip title="Total latency">
+            <span className="flex items-center text-blue-600">
+              <ClockCircleOutlined className="mr-1" />
+              {(totalLatency / 1000).toFixed(2)}s
+            </span>
+          </Tooltip>
+        )}
+
+        {/* Time to first token */}
+        {timeToFirstToken !== undefined && (
+          <Tooltip title="Time to first token">
+            <span className="flex items-center text-green-600">
+              TTFT: {(timeToFirstToken / 1000).toFixed(2)}s
+            </span>
+          </Tooltip>
+        )}
+      </div>
+
+      {/* IDs row */}
+      <div className="flex flex-wrap items-center gap-3 text-gray-500 ml-4 mt-1.5">
+        {/* Task ID */}
+        {taskId && (
+          <Tooltip title={`Click to copy: ${taskId}`}>
+            <span
+              className="flex items-center cursor-pointer hover:text-gray-700"
+              onClick={() => copyToClipboard(taskId)}
+            >
+              <FileTextOutlined className="mr-1" />
+              Task: {truncateId(taskId)}
+              <CopyOutlined className="ml-1 text-gray-400 hover:text-gray-600" />
+            </span>
+          </Tooltip>
+        )}
+
+        {/* Context/Session ID */}
+        {contextId && (
+          <Tooltip title={`Click to copy: ${contextId}`}>
+            <span
+              className="flex items-center cursor-pointer hover:text-gray-700"
+              onClick={() => copyToClipboard(contextId)}
+            >
+              <LinkOutlined className="mr-1" />
+              Session: {truncateId(contextId)}
+              <CopyOutlined className="ml-1 text-gray-400 hover:text-gray-600" />
+            </span>
+          </Tooltip>
+        )}
+
+        {/* Details toggle */}
+        {(metadata || status?.message) && (
+          <Button
+            type="text"
+            size="small"
+            className="text-xs text-blue-500 hover:text-blue-700 p-0 h-auto"
+            onClick={() => setShowDetails(!showDetails)}
+          >
+            {showDetails ? <DownOutlined /> : <RightOutlined />}
+            <span className="ml-1">Details</span>
+          </Button>
+        )}
+      </div>
+
+      {/* Expandable details panel */}
+      {showDetails && (
+        <div className="mt-2 ml-4 p-3 bg-gray-50 rounded-md text-gray-600 border border-gray-200">
+          {/* Status message */}
+          {status?.message && (
+            <div className="mb-2">
+              <span className="font-medium text-gray-700">Status Message:</span>
+              <span className="ml-2">{status.message}</span>
+            </div>
+          )}
+
+          {/* Full IDs */}
+          {taskId && (
+            <div className="mb-1.5 flex items-center">
+              <span className="font-medium text-gray-700 w-24">Task ID:</span>
+              <code className="ml-2 px-2 py-1 bg-white border border-gray-200 rounded text-xs font-mono">{taskId}</code>
+              <CopyOutlined
+                className="ml-2 cursor-pointer text-gray-400 hover:text-blue-500"
+                onClick={() => copyToClipboard(taskId)}
+              />
+            </div>
+          )}
+
+          {contextId && (
+            <div className="mb-1.5 flex items-center">
+              <span className="font-medium text-gray-700 w-24">Session ID:</span>
+              <code className="ml-2 px-2 py-1 bg-white border border-gray-200 rounded text-xs font-mono">{contextId}</code>
+              <CopyOutlined
+                className="ml-2 cursor-pointer text-gray-400 hover:text-blue-500"
+                onClick={() => copyToClipboard(contextId)}
+              />
+            </div>
+          )}
+
+          {/* Metadata fields */}
+          {metadata && Object.keys(metadata).length > 0 && (
+            <div className="mt-3">
+              <span className="font-medium text-gray-700">Custom Metadata:</span>
+              <pre className="mt-1.5 p-2 bg-white border border-gray-200 rounded text-xs font-mono overflow-x-auto whitespace-pre-wrap">
+                {JSON.stringify(metadata, null, 2)}
+              </pre>
+            </div>
+          )}
+        </div>
+      )}
+    </div>
+  );
+};
+
+export default A2AMetrics;

ui/litellm-dashboard/src/components/playground/chat_ui/ChatUI.tsx

@@ -51,6 +51,10 @@ import { fetchAvailableModels, ModelGroup } from "../llm_calls/fetch_models";
 import { makeOpenAIImageEditsRequest } from "../llm_calls/image_edits";
 import { makeOpenAIImageGenerationRequest } from "../llm_calls/image_generation";
 import { makeOpenAIResponsesRequest } from "../llm_calls/responses_api";
+import { Agent, fetchAvailableAgents } from "../llm_calls/fetch_agents";
+import { makeA2AStreamMessageRequest } from "../llm_calls/a2a_send_message";
+import A2AMetrics from "./A2AMetrics";
+import { A2ATaskMetadata } from "./types";
 import MCPEventsDisplay, { MCPEvent } from "./MCPEventsDisplay";
 import { EndpointType, getEndpointType } from "./mode_endpoint_mapping";
 import ReasoningContent from "./ReasoningContent";
@@ -124,6 +128,8 @@ const ChatUI: React.FC<ChatUIProps> = ({
   const [selectedModel, setSelectedModel] = useState<string | undefined>(undefined);
   const [showCustomModelInput, setShowCustomModelInput] = useState<boolean>(false);
   const [modelInfo, setModelInfo] = useState<ModelGroup[]>([]);
+  const [agentInfo, setAgentInfo] = useState<Agent[]>([]);
+  const [selectedAgent, setSelectedAgent] = useState<string | undefined>(undefined);
   const customModelTimeout = useRef<NodeJS.Timeout | null>(null);
   const [endpointType, setEndpointType] = useState<string>(
     () => sessionStorage.getItem("endpointType") || EndpointType.CHAT,
@@ -340,6 +346,29 @@ const ChatUI: React.FC<ChatUIProps> = ({
     loadMCPTools();
   }, [accessToken, userID, userRole, apiKeySource, apiKey, token]);
 
+  // Fetch agents when A2A endpoint is selected
+  useEffect(() => {
+    const userApiKey = apiKeySource === "session" ? accessToken : apiKey;
+    if (!userApiKey || endpointType !== EndpointType.A2A_AGENTS) {
+      return;
+    }
+
+    const loadAgents = async () => {
+      try {
+        const agents = await fetchAvailableAgents(userApiKey);
+        setAgentInfo(agents);
+        // Clear selection if current agent not in list
+        if (selectedAgent && !agents.some((a) => a.agent_name === selectedAgent)) {
+          setSelectedAgent(undefined);
+        }
+      } catch (error) {
+        console.error("Error fetching agents:", error);
+      }
+    };
+
+    loadAgents();
+  }, [accessToken, apiKeySource, apiKey, endpointType]);
+
   useEffect(() => {
     // Scroll to the bottom of the chat whenever chatHistory updates
     if (chatEndRef.current) {
@@ -469,6 +498,23 @@ const ChatUI: React.FC<ChatUIProps> = ({
     });
   };
 
+  const updateA2AMetadata = (a2aMetadata: A2ATaskMetadata) => {
+    console.log("Received A2A metadata:", a2aMetadata);
+    setChatHistory((prevHistory) => {
+      const lastMessage = prevHistory[prevHistory.length - 1];
+
+      if (lastMessage && lastMessage.role === "assistant") {
+        const updatedMessage = {
+          ...lastMessage,
+          a2aMetadata,
+        };
+        return [...prevHistory.slice(0, prevHistory.length - 1), updatedMessage];
+      }
+
+      return prevHistory;
+    });
+  };
+
   const updateTotalLatency = (totalLatency: number) => {
     setChatHistory((prevHistory) => {
       const lastMessage = prevHistory[prevHistory.length - 1];
@@ -684,6 +730,12 @@ const ChatUI: React.FC<ChatUIProps> = ({
       return;
     }
 
+    // For A2A agents, require agent selection
+    if (endpointType === EndpointType.A2A_AGENTS && !selectedAgent) {
+      NotificationsManager.fromBackend("Please select an agent to send a message");
+      return;
+    }
+
     if (!token || !userRole || !userID) {
       return;
     }
@@ -908,6 +960,20 @@ const ChatUI: React.FC<ChatUIProps> = ({
           }
         }
       }
+
+      // Handle A2A agent calls (separate from model-based calls) - use streaming
+      if (endpointType === EndpointType.A2A_AGENTS && selectedAgent) {
+        await makeA2AStreamMessageRequest(
+          selectedAgent,
+          inputMessage,
+          (chunk, model) => updateTextUI("assistant", chunk, model),
+          effectiveApiKey,
+          signal,
+          updateTimingData,
+          updateTotalLatency,
+          updateA2AMetadata,
+        );
+      }
     } catch (error) {
       if (signal.aborted) {
         console.log("Request was cancelled");
@@ -1038,11 +1104,13 @@ const ChatUI: React.FC<ChatUIProps> = ({
                   endpointType={endpointType}
                   onEndpointChange={(value) => {
                     setEndpointType(value);
-                    // Clear model selection when switching endpoint type
+                    // Clear model/agent selection when switching endpoint type
                     setSelectedModel(undefined);
+                    setSelectedAgent(undefined);
                     setShowCustomModelInput(false);
                     try {
                       sessionStorage.removeItem("selectedModel");
+                      sessionStorage.removeItem("selectedAgent");
                     } catch {}
                   }}
                   className="mb-4"
@@ -1077,6 +1145,8 @@ const ChatUI: React.FC<ChatUIProps> = ({
                 />
               </div>
 
+              {/* Model Selector - shown when NOT using A2A Agents */}
+              {endpointType !== EndpointType.A2A_AGENTS && (
                 <div>
                   <Text className="font-medium block mb-2 text-gray-700 flex items-center justify-between">
                     <span className="flex items-center">
@@ -1174,6 +1244,46 @@ const ChatUI: React.FC<ChatUIProps> = ({
                     />
                   )}
                 </div>
+              )}
+
+              {/* Agent Selector - shown ONLY for A2A Agents endpoint */}
+              {endpointType === EndpointType.A2A_AGENTS && (
+                <div>
+                  <Text className="font-medium block mb-2 text-gray-700 flex items-center">
+                    <RobotOutlined className="mr-2" /> Select Agent
+                  </Text>
+                  <Select
+                    value={selectedAgent}
+                    placeholder="Select an Agent"
+                    onChange={(value) => setSelectedAgent(value)}
+                    options={agentInfo.map((agent) => ({
+                      value: agent.agent_name,
+                      label: agent.agent_name || agent.agent_id,
+                      key: agent.agent_id,
+                    }))}
+                    style={{ width: "100%" }}
+                    showSearch={true}
+                    className="rounded-md"
+                    optionLabelProp="label"
+                  >
+                    {agentInfo.map((agent) => (
+                      <Select.Option key={agent.agent_id} value={agent.agent_name} label={agent.agent_name || agent.agent_id}>
+                        <div className="flex flex-col py-1">
+                          <span className="font-medium">{agent.agent_name || agent.agent_id}</span>
+                          {agent.agent_card_params?.description && (
+                            <span className="text-xs text-gray-500 mt-1">{agent.agent_card_params.description}</span>
+                          )}
+                        </div>
+                      </Select.Option>
+                    ))}
+                  </Select>
+                  {agentInfo.length === 0 && (
+                    <Text className="text-xs text-gray-500 mt-2 block">
+                      No agents found. Create agents via /v1/agents endpoint.
+                    </Text>
+                  )}
+                </div>
+              )}
 
               <div>
                 <Text className="font-medium block mb-2 text-gray-700 flex items-center">
@@ -1440,7 +1550,8 @@ const ChatUI: React.FC<ChatUIProps> = ({
                         )}
 
                         {message.role === "assistant" &&
-                          (message.timeToFirstToken || message.totalLatency || message.usage) && (
+                          (message.timeToFirstToken || message.totalLatency || message.usage) &&
+                          !message.a2aMetadata && (
                             <ResponseMetrics
                               timeToFirstToken={message.timeToFirstToken}
                               totalLatency={message.totalLatency}
@@ -1448,6 +1559,15 @@ const ChatUI: React.FC<ChatUIProps> = ({
                               toolName={message.toolName}
                             />
                           )}
+
+                        {/* A2A Metrics - show for A2A agent responses */}
+                        {message.role === "assistant" && message.a2aMetadata && (
+                          <A2AMetrics
+                            a2aMetadata={message.a2aMetadata}
+                            timeToFirstToken={message.timeToFirstToken}
+                            totalLatency={message.totalLatency}
+                          />
+                        )}
                       </div>
                     </div>
                   </div>
@@ -1685,6 +1805,8 @@ const ChatUI: React.FC<ChatUIProps> = ({
                       endpointType === EndpointType.RESPONSES ||
                       endpointType === EndpointType.ANTHROPIC_MESSAGES
                         ? "Type your message... (Shift+Enter for new line)"
+                        : endpointType === EndpointType.A2A_AGENTS
+                          ? "Send a message to the A2A agent..."
                           : endpointType === EndpointType.IMAGE_EDITS
                             ? "Describe how you want to edit the image..."
                             : endpointType === EndpointType.SPEECH

ui/litellm-dashboard/src/components/playground/chat_ui/chatConstants.ts

@@ -42,4 +42,5 @@ export const ENDPOINT_OPTIONS = [
   { value: EndpointType.EMBEDDINGS, label: "/v1/embeddings" },
   { value: EndpointType.SPEECH, label: "/v1/audio/speech" },
   { value: EndpointType.TRANSCRIPTION, label: "/v1/audio/transcriptions" },
+  { value: EndpointType.A2A_AGENTS, label: "/v1/a2a/message/send" },
 ];

ui/litellm-dashboard/src/components/playground/chat_ui/mode_endpoint_mapping.tsx

@@ -25,6 +25,7 @@ export enum EndpointType {
   EMBEDDINGS = "embeddings",
   SPEECH = "speech",
   TRANSCRIPTION = "transcription",
+  A2A_AGENTS = "a2a_agents",
   // add additional endpoint types if required
 }
 

ui/litellm-dashboard/src/components/playground/chat_ui/types.ts

@@ -70,12 +70,24 @@ export interface VectorStoreSearchResponse {
   data: VectorStoreSearchResult[];
 }
 
+export interface A2ATaskMetadata {
+  taskId?: string;
+  contextId?: string;
+  status?: {
+    state?: string;
+    timestamp?: string;
+    message?: string;
+  };
+  metadata?: Record<string, any>;
+}
+
 export interface MessageType {
   role: string;
   content: string | MultimodalContent[];
   model?: string;
   isImage?: boolean;
   isAudio?: boolean;
+  isEmbeddings?: boolean;
   reasoningContent?: string;
   timeToFirstToken?: number;
   totalLatency?: number;
@@ -93,6 +105,7 @@ export interface MessageType {
     detail: string;
   };
   searchResults?: VectorStoreSearchResponse[];
+  a2aMetadata?: A2ATaskMetadata;
 }
 
 export interface MultimodalContent {

ui/litellm-dashboard/src/components/playground/llm_calls/a2a_send_message.tsx

@@ -0,0 +1,413 @@
+// a2a_send_message.tsx
+// A2A Protocol (JSON-RPC 2.0) implementation for sending messages to agents
+
+import { v4 as uuidv4 } from "uuid";
+import { getProxyBaseUrl } from "../../networking";
+import { A2ATaskMetadata } from "../chat_ui/types";
+
+interface A2AMessagePart {
+  kind: "text";
+  text: string;
+}
+
+interface A2AMessage {
+  kind: "message";
+  messageId: string;
+  role: "user" | "agent";
+  parts: A2AMessagePart[];
+}
+
+interface A2AJsonRpcRequest {
+  jsonrpc: "2.0";
+  id: string;
+  method: string;
+  params: {
+    message: A2AMessage;
+  };
+}
+
+interface A2AJsonRpcResponse {
+  jsonrpc: "2.0";
+  id: string;
+  result?: {
+    kind?: string;
+    parts?: A2AMessagePart[];
+    id?: string;
+    contextId?: string;
+    status?: {
+      state?: string;
+      timestamp?: string;
+      message?: {
+        parts?: A2AMessagePart[];
+      };
+    };
+    metadata?: Record<string, any>;
+    artifacts?: Array<{
+      artifactId?: string;
+      name?: string;
+      parts?: A2AMessagePart[];
+    }>;
+    [key: string]: any;
+  };
+  error?: {
+    code: number;
+    message: string;
+  };
+}
+
+/**
+ * Extracts A2A task metadata from the response result.
+ */
+const extractA2AMetadata = (result: A2AJsonRpcResponse["result"]): A2ATaskMetadata | undefined => {
+  if (!result) return undefined;
+
+  const metadata: A2ATaskMetadata = {};
+
+  // Extract task ID
+  if (result.id) {
+    metadata.taskId = result.id;
+  }
+
+  // Extract context/session ID
+  if (result.contextId) {
+    metadata.contextId = result.contextId;
+  }
+
+  // Extract status
+  if (result.status) {
+    metadata.status = {
+      state: result.status.state,
+      timestamp: result.status.timestamp,
+    };
+
+    // Extract status message text if present
+    if (result.status.message?.parts) {
+      const statusText = result.status.message.parts
+        .filter((p: any) => p.kind === "text" && p.text)
+        .map((p: any) => p.text)
+        .join(" ");
+      if (statusText) {
+        metadata.status.message = statusText;
+      }
+    }
+  }
+
+  // Extract custom metadata
+  if (result.metadata && typeof result.metadata === "object") {
+    metadata.metadata = result.metadata;
+  }
+
+  return Object.keys(metadata).length > 0 ? metadata : undefined;
+};
+
+/**
+ * Sends a message to an A2A agent using the JSON-RPC 2.0 protocol.
+ * Uses the non-streaming message/send method.
+ */
+export const makeA2ASendMessageRequest = async (
+  agentId: string,
+  message: string,
+  onTextUpdate: (chunk: string, model?: string) => void,
+  accessToken: string,
+  signal?: AbortSignal,
+  onTimingData?: (timeToFirstToken: number) => void,
+  onTotalLatency?: (totalLatency: number) => void,
+  onA2AMetadata?: (metadata: A2ATaskMetadata) => void,
+): Promise<void> => {
+  const proxyBaseUrl = getProxyBaseUrl();
+  const url = proxyBaseUrl
+    ? `${proxyBaseUrl}/a2a/${agentId}/message/send`
+    : `/a2a/${agentId}/message/send`;
+
+  const requestId = uuidv4();
+  const messageId = uuidv4().replace(/-/g, "");
+
+  const jsonRpcRequest: A2AJsonRpcRequest = {
+    jsonrpc: "2.0",
+    id: requestId,
+    method: "message/send",
+    params: {
+      message: {
+        kind: "message",
+        messageId: messageId,
+        role: "user",
+        parts: [{ kind: "text", text: message }],
+      },
+    },
+  };
+
+  const startTime = performance.now();
+
+  try {
+    const response = await fetch(url, {
+      method: "POST",
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify(jsonRpcRequest),
+      signal,
+    });
+
+    const timeToFirstToken = performance.now() - startTime;
+    if (onTimingData) {
+      onTimingData(timeToFirstToken);
+    }
+
+    if (!response.ok) {
+      const errorData = await response.json();
+      throw new Error(errorData.error?.message || errorData.detail || `HTTP ${response.status}`);
+    }
+
+    const jsonRpcResponse: A2AJsonRpcResponse = await response.json();
+
+    const totalLatency = performance.now() - startTime;
+    if (onTotalLatency) {
+      onTotalLatency(totalLatency);
+    }
+
+    if (jsonRpcResponse.error) {
+      throw new Error(jsonRpcResponse.error.message);
+    }
+
+    // Extract text and metadata from response
+    const result = jsonRpcResponse.result;
+    if (result) {
+      let responseText = "";
+
+      // Extract and send A2A metadata
+      const a2aMetadata = extractA2AMetadata(result);
+      if (a2aMetadata && onA2AMetadata) {
+        onA2AMetadata(a2aMetadata);
+      }
+
+      // A2A Task response format with artifacts array
+      // Extract text from artifacts[*].parts[*] where kind === "text"
+      if (result.artifacts && Array.isArray(result.artifacts)) {
+        for (const artifact of result.artifacts) {
+          if (artifact.parts && Array.isArray(artifact.parts)) {
+            for (const part of artifact.parts) {
+              if (part.kind === "text" && part.text) {
+                responseText += part.text;
+              }
+            }
+          }
+        }
+      }
+      // Fallback: direct parts array (simpler response format)
+      else if (result.parts && Array.isArray(result.parts)) {
+        for (const part of result.parts) {
+          if (part.kind === "text" && part.text) {
+            responseText += part.text;
+          }
+        }
+      }
+      // Fallback: status.message.parts format
+      else if (result.status?.message?.parts) {
+        for (const part of result.status.message.parts) {
+          if (part.kind === "text" && part.text) {
+            responseText += part.text;
+          }
+        }
+      }
+
+      if (responseText) {
+        onTextUpdate(responseText, `a2a_agent/${agentId}`);
+      } else {
+        // Fallback: show raw result if we couldn't parse it
+        console.warn("Could not extract text from A2A response, showing raw JSON:", result);
+        onTextUpdate(JSON.stringify(result, null, 2), `a2a_agent/${agentId}`);
+      }
+    }
+  } catch (error) {
+    if (signal?.aborted) {
+      console.log("A2A request was cancelled");
+      return;
+    }
+    console.error("A2A send message error:", error);
+    throw error;
+  }
+};
+
+/**
+ * Sends a streaming message to an A2A agent using the JSON-RPC 2.0 protocol.
+ * Uses the message/stream method with NDJSON responses.
+ */
+export const makeA2AStreamMessageRequest = async (
+  agentId: string,
+  message: string,
+  onTextUpdate: (chunk: string, model?: string) => void,
+  accessToken: string,
+  signal?: AbortSignal,
+  onTimingData?: (timeToFirstToken: number) => void,
+  onTotalLatency?: (totalLatency: number) => void,
+  onA2AMetadata?: (metadata: A2ATaskMetadata) => void,
+): Promise<void> => {
+  const proxyBaseUrl = getProxyBaseUrl();
+  const url = proxyBaseUrl
+    ? `${proxyBaseUrl}/a2a/${agentId}`
+    : `/a2a/${agentId}`;
+
+  const requestId = uuidv4();
+  const messageId = uuidv4().replace(/-/g, "");
+
+  const jsonRpcRequest: A2AJsonRpcRequest = {
+    jsonrpc: "2.0",
+    id: requestId,
+    method: "message/stream",
+    params: {
+      message: {
+        kind: "message",
+        messageId: messageId,
+        role: "user",
+        parts: [{ kind: "text", text: message }],
+      },
+    },
+  };
+
+  const startTime = performance.now();
+  let firstChunkReceived = false;
+  let latestMetadata: A2ATaskMetadata | undefined;
+  let accumulatedText = "";
+
+  try {
+    const response = await fetch(url, {
+      method: "POST",
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        "Content-Type": "application/json",
+      },
+      body: JSON.stringify(jsonRpcRequest),
+      signal,
+    });
+
+    if (!response.ok) {
+      const errorData = await response.json();
+      throw new Error(errorData.error?.message || errorData.detail || `HTTP ${response.status}`);
+    }
+
+    const reader = response.body?.getReader();
+    if (!reader) {
+      throw new Error("No response body");
+    }
+
+    const decoder = new TextDecoder();
+    let buffer = "";
+    let done = false;
+
+    while (!done) {
+      const readResult = await reader.read();
+      done = readResult.done;
+      const value = readResult.value;
+      if (done) break;
+
+      buffer += decoder.decode(value, { stream: true });
+      const lines = buffer.split("\n");
+      buffer = lines.pop() || "";
+
+      for (const line of lines) {
+        if (!line.trim()) continue;
+
+        try {
+          const chunk = JSON.parse(line);
+
+          if (!firstChunkReceived) {
+            firstChunkReceived = true;
+            const timeToFirstToken = performance.now() - startTime;
+            if (onTimingData) {
+              onTimingData(timeToFirstToken);
+            }
+          }
+
+          // Handle streaming chunks - extract text from various A2A formats
+          const result = chunk.result;
+          if (result) {
+            // Extract metadata from each chunk (keep latest)
+            const chunkMetadata = extractA2AMetadata(result);
+            if (chunkMetadata) {
+              latestMetadata = { ...latestMetadata, ...chunkMetadata };
+            }
+
+            const chunkKind = result.kind;
+
+            // Handle artifact-update chunks (streaming response content)
+            // Note: streaming uses "artifact" (singular), not "artifacts" (plural)
+            if (chunkKind === "artifact-update" && result.artifact) {
+              const artifact = result.artifact;
+              if (artifact.parts && Array.isArray(artifact.parts)) {
+                for (const part of artifact.parts) {
+                  if (part.kind === "text" && part.text) {
+                    // Accumulate actual response content
+                    accumulatedText += part.text;
+                    onTextUpdate(accumulatedText, `a2a_agent/${agentId}`);
+                  }
+                }
+              }
+            }
+            // Handle non-streaming Task response format with artifacts array (plural)
+            else if (result.artifacts && Array.isArray(result.artifacts)) {
+              for (const artifact of result.artifacts) {
+                if (artifact.parts && Array.isArray(artifact.parts)) {
+                  for (const part of artifact.parts) {
+                    if (part.kind === "text" && part.text) {
+                      accumulatedText += part.text;
+                      onTextUpdate(accumulatedText, `a2a_agent/${agentId}`);
+                    }
+                  }
+                }
+              }
+            }
+            // Handle status-update chunks (progress messages like "Processing request...")
+            // Only show these temporarily if we haven't received actual content yet
+            else if (chunkKind === "status-update" && result.status?.message?.parts) {
+              // Skip status messages once we have real content
+              if (!accumulatedText) {
+                for (const part of result.status.message.parts) {
+                  if (part.kind === "text" && part.text) {
+                    // Show as temporary status - will be replaced when real content arrives
+                    onTextUpdate(part.text, `a2a_agent/${agentId}`);
+                  }
+                }
+              }
+            }
+            // Direct parts array (fallback)
+            else if (result.parts && Array.isArray(result.parts)) {
+              for (const part of result.parts) {
+                if (part.kind === "text" && part.text) {
+                  accumulatedText += part.text;
+                  onTextUpdate(accumulatedText, `a2a_agent/${agentId}`);
+                }
+              }
+            }
+          }
+
+          if (chunk.error) {
+            throw new Error(chunk.error.message);
+          }
+        } catch (parseError) {
+          // Only warn if it's not a JSON parse error on an empty/partial line
+          if (line.trim().length > 0) {
+            console.warn("Failed to parse A2A streaming chunk:", line, parseError);
+          }
+        }
+      }
+    }
+
+    const totalLatency = performance.now() - startTime;
+    if (onTotalLatency) {
+      onTotalLatency(totalLatency);
+    }
+
+    // Send final metadata after streaming completes
+    if (latestMetadata && onA2AMetadata) {
+      onA2AMetadata(latestMetadata);
+    }
+  } catch (error) {
+    if (signal?.aborted) {
+      console.log("A2A streaming request was cancelled");
+      return;
+    }
+    console.error("A2A stream message error:", error);
+    throw error;
+  }
+};

ui/litellm-dashboard/src/components/playground/llm_calls/fetch_agents.tsx

@@ -0,0 +1,52 @@
+// fetch_agents.tsx
+
+import { getProxyBaseUrl } from "../../networking";
+
+export interface Agent {
+  agent_id: string;
+  agent_name: string;
+  description?: string;
+  agent_card_params?: {
+    name?: string;
+    description?: string;
+    url?: string;
+  };
+}
+
+/**
+ * Fetches available A2A agents from /v1/agents endpoint.
+ */
+export const fetchAvailableAgents = async (accessToken: string): Promise<Agent[]> => {
+  try {
+    const proxyBaseUrl = getProxyBaseUrl();
+    const url = proxyBaseUrl ? `${proxyBaseUrl}/v1/agents` : `/v1/agents`;
+
+    const response = await fetch(url, {
+      method: "GET",
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+        "Content-Type": "application/json",
+      },
+    });
+
+    if (!response.ok) {
+      const errorData = await response.json();
+      throw new Error(errorData.detail || "Failed to fetch agents");
+    }
+
+    const agents: Agent[] = await response.json();
+    console.log("Fetched agents:", agents);
+
+    // Sort agents alphabetically by name
+    agents.sort((a, b) => {
+      const nameA = a.agent_name || a.agent_id;
+      const nameB = b.agent_name || b.agent_id;
+      return nameA.localeCompare(nameB);
+    });
+
+    return agents;
+  } catch (error) {
+    console.error("Error fetching agents:", error);
+    throw error;
+  }
+};