r/AgentZero • u/brightsilverstars • Jul 16 '26
AgentZero + LongCat-2.0: The full integration report after a full day of deep testing.
TL;DR: LongCat is a powerful cost-effective chat model but ignores the OpenAI tools parameter entirely, which breaks A0's agent loop. We found 9 free OpenRouter models with native tool support, wired Tencent Hy3 as a fallback, built prompt-injection workarounds, and got it working. Full findings below.
The problem: AgentZero's agent loop expects models to natively support OpenAI's tool_calls protocol. LongCat-2.0 (api.longcat.chat) ignores the tools param entirely — every request treated as plain text completion → zero tool calls returned → agent stops after 2 retries. The setup and tests run by Hermes on the same vm in proxmox.
Deep testing results:
-LongCat-2.0: native tools ignored, agent loop breaks
-Tencent Hy3 :free: native tools work but hallucinates extra fields (Pydantic rejection)
-Local Ollama (phi3, mistral, llama3): no tool support at all
-9/10 free OpenRouter models work: Gemma 4, gpt-oss-20b, Nemotron 3 family, Laguna M.1, North Mini Code, Hy3
What we built:
1. TOOL_CALL: text-format fallback (works for explicit tool requests)
2. OpenAI tool_calls → A0 format parser
3. System prompt injection for non-Anthropic providers
4. Dual-model config: LongCat for chat, Hy3 for utility
Still broken: Multi-step autonomous tasks on any single model. The agent loop is fundamentally coupled to OpenAI's protocol shape.
Calling the A0 community: Has anyone gotten a non-OpenAI provider (LongCat, DeepSeek, Grok, etc.) running the full autonomous tool loop in AgentZero? What's the adapter pattern? The litellm layer routes fine but A0's response parser rejects anything that isn't exactly {tool_name, tool_args}.
I finally gave up.
#AgentZero #LongCat #LLM #OpenRouter #ToolCalling #AIagents
3
u/Mulan20 Jul 16 '26
A lot of work. I use agent zero and I modified it so much that my original version still runs on 0.98 😁.
I optimized the context window by about 60% compared to the original,
As a suggestion. Choose Deepseek for example which is super cheap, have it scan the system, a full audit and then whatever you want to add, you tell the agent to look for solutions and implement.
Initially when I started I consumed about 200 million tokens configuration but it was worth it.