The agent is fine. The model is the problem.
Tools like REA turned reverse engineering into an agent workflow: npx rea-agents setup gives Claude Code, Codex, Cursor, Gemini CLI, OpenCode or Qwen Code an MCP server that inspects native binaries, Electron and JavaScript apps, .NET assemblies, firmware images and Unity IL2CPP metadata, with Ghidra, Hopper or IDA doing the decompilation. You ask "how does search work in this app, show me the evidence, and build me the same feature", and the agent walks the binary.
Then the model stops. Since October 21, 2026, users have reported Claude Opus 5.5 halting reverse-engineering requests mid-sentence; ChatGPT applies a similar refusal layer to decompiler output and exploit questions. The tooling did not change. The model behind it did.
LLM Gateway fixes the half you control. Keep REA, keep your agent, and put a model behind it that reads the pseudocode and keeps going.
Swap the model, keep the setup
Claude Code reads the Anthropic-compatible endpoint; everything else reads the OpenAI-compatible one. REA's MCP registration and skill are untouched.
1# Create a key in the dashboard, then in the shell you launch the agent from:2export LLM_GATEWAY_API_KEY=llmgtwy_your_api_key_here3
4# Claude Code + REA on DeepSeek V4 Pro5export ANTHROPIC_BASE_URL=https://api.llmgateway.io6export ANTHROPIC_AUTH_TOKEN=$LLM_GATEWAY_API_KEY7export ANTHROPIC_MODEL=deepseek-v4-pro8claude1# Create a key in the dashboard, then in the shell you launch the agent from:2export LLM_GATEWAY_API_KEY=llmgtwy_your_api_key_here3
4# Claude Code + REA on DeepSeek V4 Pro5export ANTHROPIC_BASE_URL=https://api.llmgateway.io6export ANTHROPIC_AUTH_TOKEN=$LLM_GATEWAY_API_KEY7export ANTHROPIC_MODEL=deepseek-v4-pro8claude1# ~/.codex/config.toml — Codex + REA on Kimi K3.1 Pro2model = "kimi-k3.1-pro"3model_provider = "llmgateway"4
5[model_providers.llmgateway]6name = "LLM Gateway"7base_url = "https://api.llmgateway.io/v1"8env_key = "LLM_GATEWAY_API_KEY"9wire_api = "responses"1# ~/.codex/config.toml — Codex + REA on Kimi K3.1 Pro2model = "kimi-k3.1-pro"3model_provider = "llmgateway"4
5[model_providers.llmgateway]6name = "LLM Gateway"7base_url = "https://api.llmgateway.io/v1"8env_key = "LLM_GATEWAY_API_KEY"9wire_api = "responses"Every model on the reverse engineering models page supports tool calling, so analyze-javascript-application, the Ghidra bridge and the Hopper bridge all work as MCP tools.
Fit the whole binary in context
A Ghidra export of a mid-sized native binary — pseudocode, strings, cross-references — runs to hundreds of thousands of tokens. On a 128K model the agent reads a window and guesses at the rest. DeepSeek V4 Pro, Kimi K3.1 Pro, GLM-5.2 and Qwen3.7 Max hold a million tokens, so the model sees every call site of the function it is renaming. Prompt caching means the second, third and fiftieth question about the same export does not pay full price for the export again.
Run the cheap pass cheap
Most of an RE session is bulk work: naming functions, classifying strings, summarising what each module imports. That belongs on DeepSeek V4.1 Flash at $0.15 per million input tokens, not on a frontier model. Route the bulk pass to a budget model, escalate the final explanation or reimplementation to a stronger one, and read the per-request ledger to see exactly what the binary cost you. A model ID without a provider prefix can also retry on another eligible provider during an outage; that only helps for models served by more than one provider, so check the provider count on the models page before planning an overnight trace.
Stay on the right side of the line
Analysing your own code, open-source software, malware in a sandbox and CTF challenges is generally legal, and interoperability and security research carry explicit exemptions in many jurisdictions. Copying closed-source code into a product, circumventing DRM, or poking at systems you do not own usually is not, and the answer depends on your jurisdiction and the licence. A community member in REA's discussions wrote a plain-language guide to what needs permission; it is not legal advice, but read it before you publish.
Get started
Create a key, set a base URL, pick a model from the reverse engineering list, and run the same REA prompt that stopped yesterday.